Introduction

The zeolites are a rather large group of minerals and favorites with collectors. As a group they are common and widespread around the world. They occur in a wide variety of shapes and habits. While generally pale in color, they can be red, orange, or green. Famous zeolite localities include Scotland, Iceland, New Jersey, the American Northwest, and many others. Until overshadowed by the discovery of zeolites in the enormous Deccan basalts of India in the mid 1900s, the Bay of Fundy region was world famous for its zeolites. While many of the world's greatest zeolites have since been found in India, the Bay of Fundy still offers several world class zeolites that are rare in India including chabazite, gmelinite, analcime, natrolite, and thomsonite.

In addition to the basalt localities along the Bay of Fundy, zeolites and the associates have also been found along the Cobequid Pass, Clarke Head, the McCoy Brook Formation at Ross Creek, and the East Kemptville Mine. Also at Deep Cove, Scotch Lake, and near Malagawatch, all in Cape Breton.

So what exactly is a zeolite? Zeolites are a class of materials with a regular structure of voids within their molecular structure. The word 'zeolite' comes from the Greek zeo (to boil) and lithos (stone). This is because many zeolites contain significant amounts of water within their structure. This water is lost when they are heated, but much of it is regained when they are cooled - depending of the species. Zeolites have a number of beneficial properties and are widely used in industry. The voids in their structure can be used as a molecular sieve and can be used to sort other molecules by size. One major application is in the processing of petrochemicals. Another application is to absorb ammonia molecules, and thus smell, from cats' litter boxes. Many zeolites are now man-made, but natural zeolites are also used in some applications. The number of naturally occurring zeolites is actually quite large with over 60 recognized species. However, about half of these have only ever been found as tiny microcrystals and many are quite rare.

In 1997 the International Mineralogical Association redefined the minerals within the zeolite group. As such, many minerals familiar to collectors, such as stilbite and heulandite ar technically no longer mineral species. Rather they are group names with several species defined according to the most abundant element (e.g. stilbite-Ca, stilbite-Na, stilbite-K). Because there is no way to tell these apart visually, the group name are used below, where applicable.

Table 1: Zeolites found in Nova Scotia.

Analcime - NaAlSi₂O₆·H₂O

Morphology

This is one of the most easily recognizable zeolites, because of its distinctive shape. Often described as 'soccer ball' shaped, the proper name is the trapezohedron. A complete free-floating crystal would have 24 sides. The crystal structure of analcime is cubic, though the cube form is rare in analcime. I have, however, collected examples with small cube faces at Wasson's Bluff.

     

The images below show a crystal with selected edges bevelled. In this case the the typical trapezohedron is being modified with the trisoctahedron {233}. According to Tschernich (1992) it appears that this morphology has only been found once before, at the Boylstone Quarry, Glasgow, Scotland as report by Heddle (1901). When a bevel is examined under high magnification, an uneven line can be seen running down the middle of it, as if the material grew in from either side.

Colors

Analcime is typically white but can be red, pink or brown. McKay Head and Two Islands have produced crystals that are heavily included with chlorite and are thus green. A specimen from Cape Split shows water-clear crystals that appear green due to the underlying celadonite.

Inclusions and Pseudomorphs

At both Wasson's Bluff and Cape D'Or, native copper is sometimes found with the analcime. At Wasson's sharp bright and lustrous microcrystals of copper have been found scattered around inside the analcime without any attachment to the underlying matrix. The copper included analcime crystals, or at least parts of the crystals, often fluoresce a bright blue color. This property was discovered by local collector Terry Collett.

Excellent specimens of analcime after stilbite have been found at Five Islands. Some specimens show the process stopped midway, with both stilbite (although somewhat altered) and pseudomorphs on the same specimen. Most of the stilbite that was replaced did not have a lot of relief, but a few specimens show a nice sheaf structure. In some cases, small cavities remain inside the pseudos, and natrolite is found growing in these little hollow spaces. In other cases, the replacements are solid analcime.

Range and Non-'North Mountain Formation' Occurrences

An example of a zeolite NOT from the Bay of Fundy, analcime pseudomorphs after phillipsite have been reported from near Malagawatch, Cape Breton. They are unusual for several reasons. The first is that phillipsite as never been reported, either as phillipsite or pseudomorphed, from Nova Scotia before. Secondly, they were found in Cape Breton, this being the first report to my knowledge of zeolites in Cape Breton. Finally the zeolite formed in a limestone - unusual for Nova Scotia. They form single crystals and crystal clusters, 3 to 7 mm in size, and constitute up to 7% of the volume of the rock in which they form. They tend to have a pitted surface due to inclusions of carbonates which are etched away when the specimens are removed from the host rock. A photo is shown on the 'Pseudomorphs' page.

Another example of analcime not from the basalts is the unsuual assemblage at Clarke Head. Here analcime is a rock forming mineral with scapolite, hematite, rutile, titanite, and calcite.

Chabazite - CaAl₂Si₄O₁₂·6H₂O

Morphology

Chabazite is distinctive when it forms simple rhombohedral shaped crystals. The angles of the rhomb are about 94 degrees, making them appear to be nearly cubes at a quick glance. The drawing below shows rhombs that are increasingly modified by higher order forms. Simple rhombs indicate the lowest temperature of formation; modifications indicate higher temperatures.

Chabazite is an an example of a mineral that is very frequently twinned. Even simple rhombs are often internally twinned, which is observed in striations that change directions on a given face. More conspicuous are penetration twins. Pictured below is a beautiful example from Cape D'Or. Note the little corners of the twin sticking through the front face of the primary crystal. While penetration twins are extremely common in chabazite, contact twins are much more difficult to find. The lower photo below shows a contact twin from Wasson's Bluff. Unlike the penetration twins, be can draw a plane through this twin with the primary crystal on one side of the plane and the twin on the other side (the designation of primary and twin is arbitrary). The angle between the two halves is quite large.

Colors

The classic chabazite from Nova Scotia comes from Wasson's Bluff where is forms excellent orange crystals. Darker red crystals have also been found and were at one time given the varietal name of acadialite, but this term should be avoided. The ranges of colors is considerable, including white, pink, orange, various shades of red, and brown.

Inclusions

Chabazite is sometimes found included with other minerals such as native copper, celadonite, and goethite. These sometimes make interesting and colorful specimens.

Range

Chabazite is common along the north side of the Bay of Fundy (ex. Wasson's Bluff, Cape D'Or, Partridge Island). It is uncommon at Capes Blomidon and Split. It is not found along the shoreline of the eastern half of the North Mountain, but it is found on the top of the mountain in places. It is also reported from the Digby area and I have seen it from Sandy Cove.

Epistilbite - CaAl₂Si₆O₁₆·5(H₂O)

Epistilbite was reported by How (1858) but he later doubted the identification, thinking instead it was heulandite (Marsh 1863). Bray (1986) reported epistilbite from several localities including Brown Mountain Road, Viewmont, Garland, Grafton, Pelton Mountain, Glenmont, and North Arlington Road, using X-ray diffraction and thin section. Epistilbite was identified by Pe-Piper (2000) from Ross Creek. It would appear that these reports are all by slicing samples; I am not aware of any free standing crystals of any size.

The specimen figured below is the sample Z650 from Pe-Piper (2000). It is a small amygdale that was sliced, revealing three very distinct zones; an outer zone of mordenite and an inner zone of epistilbite, separated by a dark zone with Fe–Mg–Na aluminosilicates and mordenite. In the paper, the X-ray results are presented in Figure 6B, however it appears that 'Zone 3 mordenite' should read 'Zone 3 epistilbite'. Below, I've shown the XRD results for the epstilbite from that paper, in black, and compared them to XRD data for epistilbite from Iceland, collected by RRUFF (red, https://rruff.info/Epistilbite), and simulated data from the International Zeolite Association (Treacy and Higgins, 2001). It is clear that there is a good correlation between the peaks of the three data sets. The data sets are aligned by angle, but the vertical scale is somewhat arbitrary and the curves are offset to make them more visible.

Gmelinite - Na₂CaAl₂Si₄O₁₂·6H₂O

Morphology

Gmelinite is a somewhat rare zeolite that can be confused with chabazite. In the classic habit it forms what are described as 'UFO-shaped' crystals. They are six sided (hexagonal) terminated on either end in a shallow six sided pyramid. The confusion with chabazite arises from three problems. First, the gmelinite crystals found in the Amethyst Cove area are distorted so that alternating pyramidal faces are very tiny. The overall appearance of the crystal becomes rhombohdral, like a chabazite crystal. Secondly, twinned chabazites can often form a somewhat UFO-like shape with what appear to be six prism faces and shallow pyramidal terminations. Third, at places such as Two Islands and Five Islands, the gmelinite has grown as a thin layer over partially to mostly eroded chabazite. The result is a crystal with an overall rhombic shape, but with tiny lustrous triangular growth faces all over the crystal.

Range

The range for gmelinite is much more restricted than most of the other zeolites. It is common at Five Islands, Two Islands, Capes Blomidon and Split, amd rare at Wasson's Bluff. I'm not aware of it being found anywhere else in Nova Scotia. All of those locations are in the north-east portion of the North Mountain Formation.

At Two Islands and Five Islands specimens of gmelinite on chabazite can be found. As described in the literature, the gmelinite forms a thin colorless shell over the pink to salmon colored chabazite, forming an epimorph. The chabazite is partly to mostly dissolved away, leaving a foamy textured interior. The gmelinite on the other hand is extremely lustrous and can be identified by the triangular growth hillocks that it forms.

Color

Gmelinite from Nova Scotia is nearly always a pale pink to pale orange color. Some examples from Cape Blomidon are creamy white and fluoresce a brilliant lime-green color under long-wave ultraviolet light. The spectrum of the fluorescence has a series of very distinctive peaks that indicate the activator is the uranyl ion.

Heulandite - (Ca_0.5,Na)₉Al₉Si₂₇O₇₂·24(H₂O) and
Clinoptilolite - (Ca_0.5,Na)₆Al₆Si₃₀O₇₂·20(H₂O)

Morphology

With stilbite, heulandite is one of the most common zeolites found in the region. It is found at nearly every locality. Along the North Mountain, it generally forms very fine druses of orange crystals. At Amethyst Cove, large brownish crystals are found. At Wasson's Bluff, the crystals are colorless to white and very pearly in luster. For the micro collector, bright yellow gemmy crystals are found at Swan Creek.

It is useful to compare the crystal drawing of Walker and Parsons to the photograph. The drawing nicely exemplifies why the crystals of heulandite are referred to as coffin-shaped in many books (face a is the top of the coffin). However, in the vast majority of heulandite from Nova Scotia, the endfaces c are extremely tiny or non existent. Likewise, the m form is very tiny. The result is a simple rhombic prism. Further, heulandite often forms druses of crystals and only the top half of each crystal is visible, resulting in a wedge shape. When I first began collecting, these wedges, which were clearly not coffin shaped, caused me great confusion.

The heulandite crystals tend to be simple in form, producing what appear to be rhombic prisms, with only small modifying faces. On a few occasions some very unusual heulandites have been found that are greatly exaggerated in the [010] direction with a strong {110} form, such that the crystals are disk shaped. The photo below shows an example, but it is difficult to capture in a photo.

Heulandite sometimes likes to form curved, twisted crystals reminiscent of dolomite. The sample shown below is example of this habit. In addition it is a compound crystal, with many little heulandite crystals forming the larger curved crystal. Difficult to capture in a photo. In some extreme cases, the heulandite has curved so much that it has formed rounded, layered blister-like formations. The material can be easily mistaken for chalcedony at first glance, but on close inspection openings in the 'blisters' show the heulandite crystal faces.

Chemistry

The difference between heulandite and clinoptilolite is in the ratio of Si:Al. These two minerals are the only zeolites to be given separate identities based on this ratio, and it was defined this way only because the two names were already widely used in literature. In heulandite Si:Al < 4.0 and in clinoptilolite Si:Al >= 4.0; a continuous series is formed between the two. Visually they are indistinguishable. Clinoptilolite has been reported from the Arlington Quarry, identified through microprobe analysis (Pe-Piper).

Colors

Range and Non-'North Mountain Formation' Occurrences

Considering places other than the North Mountain Formation where heulandite is found, an interesting one is the East Kemptville Tin Mine. Here I've found two specimens of white crystals that have been identified as heulandite/clinoptilolite. They are associated with pyrite.

 
Laumontite - CaAl₂Si₄O₁₂·4H₂O

Morphology

This mineral is most common along the North Mountain in the area of Harborville to Margaretsville. Great seams and pockets are full of it. Unfortunately, when this mineral is exposed to the atmosphere, it quickly loses water. In as short as a day, it turns from beautiful fans of crystals into a powdery mass. For very fresh material, though, the time is a bit longer and a collector can get it home in time to preserve it, especially if it is wrapped in plastic or wet paper on the beach. At home, a nice specimen can be stored indefinitely in an airtight container with some moisture added.

Laumontite rarely forms individual crystals, preferring instead to form small groups of diverging crystals, almost like brushes. The color varies from colorless with hints of purple, to orange and white. They can be transparent when fresh but on drying they turn chalky white. The photo below shows an very unusual specimen in that the divergent sprays have gone to the extreme and formed balls. The orange color is also unusually intense.

Below is shown a crystal drawing of a rare single crystal. Walker and Parsons state that the form indicated on the drawing as q is new and is approximately (12.1.11). The other forms are m(110), e(101), and c(001).

Even with the tremendous amount of laumontite found in the province, no twinned laumontite crystals are reported in the historical literature. In 2021, Terry Collett found a pocket with many "swallow tail" twins, which are twinned on {100} and produce notches at the end of the crystals. They were transparent when collected. Tschernich (1992) writes that such twins are common, but based on photos submitted to Mindat.org, they do not seem to be, with the exception of the Bishop Mining District in California which is a classic laumontite locality with huge crystals that are nearly always twinned.

Range and Non-'North Mountain Formation' Occurrences

Laumontite has been found at just about every main locality around the Bay of Fundy, even if in very small amounts. Along the North Mountian, however, it is abundant, to the point where it might be locally the most abundant zeolite. Great seams and veins of it exist along the stretch from Hall's Harbour to Margaretsville.

An early specimen in my collection is a piece of limestone from the McCoy Brook Formation east of Ross Creek, with calcite and laumontite crystals. I have not heard of zeolites reported from those rocks before and it is a rare example of zeolites from limestone in Nova Scotia.

Mesolite - Na₂Ca₂Al₆Si₉O₃₀·8H₂O

Morphology

Mesolite is one of the white needle-like zeolites that are the cause of considerable headaches for those interested in knowing exactly what mineral they have. The general problem is that there are several white needle-like zeolites that can be difficult for the ameteur to distinguish. In general these include mesolite, mordenite, natrolite, thomsonite, and scolecite. The more serious problem is that mesolite, natrolite, and scolecite can all be found in what appears to be a single crystal! They are often found growing in layers, switching from one mineral to the next from the core to the exterior of the crystal, with no way to visually distinguish the constituants. Even with sophisticated equipment, it can be hard to tell these apart. Some general comments can be made to simplify the situation here in Nova Scotia, but even so, they should be considered rules of thumb rather than laws.

The mineral is found frequently at Cape D'Or as balls and pocket linings of very fine crystals. It is very fine grained, and is easily damaged by touching the crystals. The crystals will also become matted when exposed to water. Often, when found, the mesolite will already have encountered rainwater and fresh pockets are rare.

While the Cape D'Or material is visually distinctive from the other similar zeolites, material from the North Mountain is not. Walker and Parsons explain that material from that area forms larger, robust crystals that visually appear to be natrolite but when tested always turned out to be mesolite. The specimen beow is an example from this area, but has not been tested.

From Cape D'Or mesolite has been found pseudomorphing another mineral, in this case analcime. A few of the specimens have been found and are very interesting and sharp replacements. The specimen shown below was a solid nodule that was broken open to reveal the pseudo. Note the dirty area on the right side; it's a mass of mesolite fibers in an otherwise empty void left by an earlier analcime crystal.

Mordenite - (Ca,Na₂,K₂)Al₂Si₁₀O₂₄·7H₂O

Morphology

In 1858, Henry How discovered a new zeolite to the east of Black Rock. He named it mordenite, for the small community of Morden, which was nearby. How says of the mineral,

It occurs in rather small masses, varying in size from the size of a pigeon's to that of a bantam's egg, in the form of somewhat cylindrical, reniform, or flattened geodes and solid concretions, rather smooth externally, sometimes coated with a thin, yellowish crust, blotched with a green mineral, probably a silicate of iron, and sometimes exposing its own white, yellowish, or pinkish-coloured surface; often a small portion of the latter only is visible.

Walker reports in 1922, that mordenite is found from Harbourville to Chute Cove, with the best localities being "to the west of Margaretville and for a couple of miles to the east of Morden". Interestingly, he goes on to say,

The writer spent several days in the localities where How obtained the type material, and found only a very small amount of mordenite. It is a matter of surprise that How suspected the individuality of this mineral and that he was able without the aid of heavy solutions or thin sections for microscopic examination to secure material sufficiently pure to permit him to indicate the fundamental properties of his new mineral.

It has since been found as fabulous specimens of hairlike needles from other parts of the world, but at this locality, display specimens cannot be found. Instead the material is restricted to massive fillings of small vugs, often intergrown with other minerals.

Natrolite - Na₂Al₂Si₃O₁₀·2H₂O

Introduction and Relationship

The name 'natrolite' was given because it is a sodium zeolite, and the Latin word for sodium is natrium. It is often found associated with another sodium zeolite, analcime. Natrolite is one of the so-called needle zeolites, along with mesolite (containing both calcium and sodium) and scolecite (containing calcium). In general it is not possible to sight-distinguish natrolite and mesolite, but geography helps a lot. A polarizing microscope can also distinguish the two. From some worldwide localities the needle zeolites can grow on top of each other, such that what appears like a single-species crystal is zoned with more than one of the species. I don't think that this has been studied in Nova Scotian examples, but at Cape Split there are specimens that consist as a thin shell of natrolite needles growing over a large ball of mesolite.

Morphology

Range

Excellent natrolite specimens have been found from several localities in Nova Scotia including Wasson's Bluff, Five Islands, and Amethyst Cove. It is not abundant, but common enough that a it can be found with some perseverance. These localities are all at the northeastern end of the North Mountain Formation. Further west at Cape D'Or, natrolite is also found, but it is less common than mesolite. And to the southwest, along the shore of the North Mountain, what visually appears like natrolite has been found to be mesolite.

Other

Wolfgang Franz von Kobell developed a fusibility scale for minerals in the 1800s. The scale has six levels with natrolite having a fusibility of 2.0-2.5. Thin crystals or fragments can be made to fuse to a clear glass in a candle flame. The picture below picture shows the tip of a crystal that was held in the top of a candle flame with tweezers. The clear glass has beaded on the end of the crystal.

Scolecite - CaAl₂Si₃O₁₀·3(H₂O)

Walker and Parsons report scolecite from the east side of Digby Gut as creamy white radiating masses to about 10 cm. Identification is supported by chemical and optical analyses. Pe-Piper (2002) reports it from Arlington Quarry using XRD and electron microprobe.

The Canadian Museum of Nature has a large XRD-confirmed specimen (CMNMC 39328). This specimen is recorded to have come from Ward’s Scientific and also has a label from the Williams College Collection (MA USA). The locality is simply Nova Scotia, but it could be from the Digby area. It is quite large (approx 20 cm across) and bright white but has only rough terminations.

Stilbite - NaCa₄Al₈Si₂₈O₇₂·30H₂O

Morphology

This is Nova Scotia's provincial mineral, and with good reason. Stilbite is found in nearly every nook and cranny of the Bay of Fundy basalt. It comes in a variety of colors and habits. It is commonly described as occurring in a wheat-sheaf habit, but this can be misleading. It can also form drusy plates with little crystal form or sharp individual bladed crystals. Colors include bright orange, brown, cream, white, and colorless.

Pseudomorphs of stilbite after mesolite have been found at Cape D'Or. The stilbite formed a thin hemispheric druse over balls of mesolite. Later, most of the mesolite dissolved away leaving a mostly hollow shell of stilbite.

Range and Non-'North Mountain Formation' Occurrences

In the North Mountain formation, stilbite is nearly ubiquitous and is associated with all of the other species. It is also found in several other locations including overlying McCoy Brook formation, the East Kemptville tin mine, and the Cobequid Pass. Stilbite/stellerite was common at East Kemptville at the time the mine closed, forming large vein surfaces, associated with purple fluorite and a bit of pyrite.

Thomsonite - NaCa₂Al₅Si₅O₂₀·6H₂O

Morphology

This mineral is less common than most on this list and generally restricted to small crystals forming drusy pocket linings or tiny tufts. It is more variable in appearance than many of the other zeolites. When terminated crystals are present, it can be distinguished from natrolite, mesolite, and scolecite because the crystals are lath-shaped (length>>width>>thickness). On the other hand, natrolite and mesolite have a square cross section.

Range

At Wasson's Bluff micro sized balls of thomsonite have been found with natrolite. In the hand, they look like nondescript white blobs, but they are nice under the microscope. Far larger specimens have been found at Cape D'Or where it has been found in a variety of habits. These include tight grayish-white translucent balls to about one centimeter across and coarser larger balls to many centimeters, which is quite large from this mineral.

Excellent examples of thomsonite have also been found in the North Mountain at various localities such as Halls Harbour, Harbourville, and near Margaretsville.

The Zeolite Associates

The zeolite associates are chemically similar to the zeolites, form under the same conditions, and are usually found with the zeolites. However, they don't satisfy the chemical and structural definition of a zeolite. Examples from Nova Scotia include apophyllite, prehnite, pectolite, gyrolite, and okenite.

Apophyllite - KCa₄(Si₄O₁₀)₂F·8H₂O

Apophyllite is commonly found in certain areas of the Bay of Fundy. It has been found at Cape D'Or, Amethyst Cove, Harborville, Isle Haute, and other places. Historically, localities such as Harbourville and Isle Haute are often listed as yielding abundant excellent specimens, however only a small amount of poor quality material remains today. It is also a difficult mineral to collect because it cleaves very easily. These facts make top quality specimens difficult to find. Still, good and interesting specimens can be found.

Below is a crystal drawing by Walker and Parsons of a crystal from Isle Haute. The forms observed were a{100}, c{001}, y{130}, p{111}, i{011}, and q{678}. They explain that the form i was difficult to measure and that the indices given for q are only an approximation.

The three most commonly observed forms are {100}, {001}, and {111} and these can combine to different degrees to produce a variety of crystal shapes. Three examples below demonstrate how a crystal can be prismatic, blocky or equant, or tabular. All three of these shapes have been found in Nova Scotia. Of the three the prismatic style is rare here, in great contrast to India where countless magnificent prismatic crystals have been found. The tabular form of apophyllite indicates a high temperature of formation and slower growth (Kostov 1975, Deer et al. 2009).

Excellent large, green and milky-white mottled crystals have been found in past decades. In the 1960s or 1970 a find by local collectors produced a number of high quality specimens. Shown below is one of those specimens collected by Harry Crosman.

Apophyllite is frequently encountered today in the area of Cape D'Or. As matte white and modified tabular crystals with red inclusions growing on stilbite. Also as excellent glassy green crystals associated with thomsonite and stilbite. As large rather blocky milky crystals with high luster. Finally, as rounded masses composed of clusters of divergent crystals associated with stilbite.

Apophyllite has also been identified from the metamorphic rocks at Scotch Lake Quarry in Cape Breton, and I have a nice specimen found in the rocks along the Cobequid Pass highway. The Cobequid Pass crystals are interesting because they are more prismatic than we see from the Bay of Fundy. They also show nice striations parallel to the long axis.

Gyrolite - NaCa₁₆Si₂₃AlO₆₀(OH)₈·64H₂O

Gyrolite was first reported from this locality by How 1861. At the time it was a very rare mineral, having only been reported from a couple other localities. How states:

I met with it in Anapolis [sic] County, N. S., some 25 miles S. W. of Cape Blomidon, between Margaretville and Port George, on the surface of fractured crystalline apophyllite, and, on further breaking the mass a good many spherical concretions of pearly lustrous plates were observed in the interior, of sizes varying from that of a pin's head to nearly half-an-inch in diameter.

Some of the numerous cavities in the apophyllite were empty, some entirely filled with gyrolite, and in others separate plates of this mineral were standing edgewise, leaving vacant spaces, while upon and by the side of the plates were in some cases rhombohedral crystals which proved to consist of calcite and were sometimes present alone in the cavities, which varied from being quite shallow to half an inch in depth.

There is a specimen in the Yale mineral collection (catalog number YPM MIN 022658, Online) and another in the Canadian Museum of nature collection (CMNMC 40536). The latter was collected at Chipman Brook, near Hall's Harbour. As collected, it was a solid pocket with small gyrolites and otherwise filled with montmorillonite. On the broken surfaces the gyrolite forms small radial aggregates that are fairly nondescript. They could easily be overlooked; perhaps the mineral is more common than is reported.

Okenite - Ca₁₀Si₁₈O₄₆·18H₂O

The best examples of this mineral in the world come from India where it forms what look like delicate puff balls or cotton balls, the needles so delicate that a touch will destroy them. In the literature, okenite has been reported from Nova Scotia only once, by Walker and Parsons in 1922. Their specimen came from east of Morden and was about 6 cm in size. In that case, however, it was very compact and tough.

In 2019 I found a couple specimens from Canada Creek and Black Rock that turned out to be likely okenite, based on EDS and powder XRD. Are are certainly not zeolites, because they lack aluminum. Remaining discrepancies include some magnesium in the EDS and a couple missing peaks in the XRD. Both specimens were found as nodules/tubes in dense basalt a couple meters below the amygdaloidal zone and isolated from other mineralization.

Pectolite - NaCa₂(HSi₃O₉)

I have a specimen with a mineral that analyzed as pectolite, associated with apophyllite, that was supposed to be from the Bay of Fundy, but I cannot be sure of the locality. Pectolite has also been found at the Scotch Lake Quarry in Cape Breton.

Prehnite - Ca₂Al₂Si₃O₁₀(OH)

Marsh writes that it had been reported from Black Rock and near Clark's Head (McKay's Head is nearby and might be the locality) but doubted its existence. Those reports have been passed down through various references, maintaining the claim. However, I have never seen a specimen of prehnite from the Bay of Fundy or any analytic evidence to support it being found there.

While not basalt, the rock of the Cobequid Pass has produced small amounts of several zeolites. More importantly, prehnite has been found as nice masses and as very sharp microcrystals. The masses were a nice translucent pistachio green color, while the crystals were more beige in color.

Prehnite has also been identified as microcrystals from Deep Cove, Cape Breton. The crystals are transparent and very sharp. Such well formed crystals of prehnite are rare worldwide.

Acknowledgements

Thanks to Ch. Baerlocher for the use of the zeolite structure drawings and to Doug Wilson for the mesolite on chabazite photo. Thanks also to Dr. Georgia Pe-Piper for the copy of the hard to find Walker and Parsons publication and to Volker Betz for the Hoffmann paper.

Conclusions

The Bay of Fundy region of Nova Scotia has been known for centuries as a producer of world class zeolites. Since the 1970s, India has become the world's most prolific source for many zeolites, but fine examples from Nova Scotia can still be found. In addition, several species found here are rare in India including chabazite, thomsonite, analcime, and natrolite. For these reasons, and the fact that the world's highest tides continually expose new material, Nova Scotia will remain a world class zeolite locality. There are also some interesting non-Fundy-basalt zeolites too. While not display quality, they produce some unusual associations and other interesting qualities.

References

Baerlocher, C., and McCusker, L.B., Database of Zeolite Structures: http://www.iza-structure.org/databases/

Bray, A. D. (1986) Zeolites and secondary minerals in the amygdaloidal zone of the basal flow, North Mountain badalt, King's County, Nova Scotia. B.Sc. Thesis, Acadia University.

Coombs, D., A. Alberti, T. Armbruster, G. Artioli, C. Colella, E. Galli, J. Grice, F. Liebau, J. Mandarino, H. Minato, E. Nickel, E. Passaglia, D. Peacor, S. Quartieri, R. Rinaldi, M. Ross, R. Sheppard, E. Tillmanns, G. Vezzalini, (1997) "Recommended Nomenclature for Zelite Minerals: Report of the Subcommittee on Zeolites of the International Mineralogical Association, Commission on New Minerals and Mineral Names", The Canadian Mineralogist, vol. 35, pp. 1571-1606. PDF

Deer, W.A., Howie, R.A., Zussman, J. (2009) Rock Forming Minerals: Layered Silicates Excluding Micas and Clay Minerals, Volume 3B. Geological Society of London, 314 pages. [Online 2020]

(to get) Heddle, M.F. (1901) The Mineralogy of Scotland. Edingburgh, V2, pp. 110-112.

Hoffmann, E. (1832) "Zerlegung einiger Chabazite", Annalen der Physik und Chemie, pp. 495-498.

How, H. (1858) "Chemical Analysis of Faroelite and some other Zeolites occurring in Nova Scotia", American Journal of Science and Arts, Second Series, Vol. XXVI, No. LXXVII, Art. IV, pg. 30. [Online 2011]

How, H. (1861) "On Gyrolite Occurring with Calcite in Apophyllite in the Trap of the Bay of Fundy," American Journal of Science, Second Series, vol. 32, no. 94, Article 3. [Online 2014]

How, H. (1863) "On Mordenite, a New Mineral from the Trap of Nova Scotia," Quarterly Journal of the Chemical Society, Article 11, pp. 100-104, 1863. [PDF]

Howe, A.B. (1876) "On Gmelinite from Nova Scotia", American Journal of Science, Series 3, vol. 12, Article 33, pp. 270-274. [Online 2015]

(to get) Kostov, I. (1975) Apophyllite morphology as an example of habit modification of planar crystals. Neues Jahrbuch für Mineralogie Abhandlungen: 123(2): 128-137.

Marsh, B.A. (1863) "Catalogue of Mineral Localities in New Brunswick, Nova Scotia, and Newfoundland", American Journal of Science, Series 2, Vol. 35, pp. 210-218. [Online 2012]

Pe-Piper, G. (2000) Mode of occurrence, chemical variation and genesis of mordenite and other associated zeolites from Morden, Nova Scotia. Canadian Mineralogist, vol. 38, p. 1215-1232. [Online 2020]

Pe-Piper, G. and Miller, L. (2002) Zeolite minerals from the North Shore of the Minas Basin, Nova Scotia. Atlantic geology, vol. 38, no. 1. [Online 2014]

Pirsson, L.V. (1891) "Gmelinite from Nova Scotia", American Journal of Science, vol. 42, no. 247, Article 8, pp. 57-63. [Online 2015].

Tschernich, R.W. (1992) "Zeolites of the World", Geoscience Press, Phoenix. [Online 2015]

von Bitter, Peter H., and Plint-Geberl, Hilary A. (1980) "Phillipsite Altered to Analcime in Basal Windsor [Shallow-water Marine] Carbonates of Mississippian Age in Nova Scotia", Canadian Journal of Earth Science, vol. 17, pp. 1096-1100.

Walker, T.L., and Parsons, A.L. (1922) "The Zeolites of Nova Scotia", Contributions to Canadian Mineralogy, University of Toronto Press, pp. 13-73.

Disclaimer: This page is intended for information purposes only. The localities described are not necessarily open to collecting and are not necessarily safe.