THE MINERAL STILBITE
- Chemistry: NaCa2Al5Si13O36 -14H2O, Hydrated sodium calcium aluminum silicate
- Class: Silicates
- Subclass: Tektosilicates
- Group: Zeolites
- Uses: mineral specimen and chemical filter
Specimens
Stilbite's structure has a typical zeolite openness about it that allows large ions and molecules to reside and actually move around inside the overall framework. The structure contains open channels that allow water and large ions to travel into and out of the crystal structure. The size of these channels controls the size of the molecules or ions and therefore a zeolite like stilbite can act as a chemical sieve. Stilbite's structure contains rings of alumino-silicate tetrahedrons oriented in one direction and this produces the prominant pinacoid faces, the perfect cleavage and the unique luster on those faces.
PHYSICAL CHARACTERISTICS:
- Color is pink or white; also tinted yellow and red.
- Luster is vitreous to pearly especially on the prominant pinacoid and cleavage surfaces.
- Transparency: crystals are transparent to mostly translucent.
- Crystal System is monoclinic; 2/m
- Crystal Habits include platy often thin crystals that can aggregate together into a wheat sheaflike structure. The prominant pinacoid is sometimes but rarely modified by other pinacoid and prism faces. Cruciform (cross-like) twins can also be found. Also forms radiating nodules.
- Cleavage is perfect in one direction parallel to the prominant pinacoid.
- Fracture is uneven.
- Hardness is 3.5 - 4.
- Specific Gravity is approximately 2.2 (very light)
- Streak is white.
- Associated Minerals are quartz, calcite, babingtonite, apophyllite, heulandite, natrolite and other zeolites.
- Notable Occurrences include Poona, India; Scotland; Iceland; New Jersey and Nova Scotia, Canada.
- Best Field Indicators are crystal habit, luster, density and associations.
 Amethyst Galleries' Mineral Gallery MINERALS |
STILBITE specimen stl-4
$ 90.00
$ 90.00
Dims: 7.4" x 5.4" x 1.8"(18.8 x 13.7 x 4.6 cm)
Wt: 13.6 oz.(385 g)
Nasik, India
At least 30 small, "wheat sheaf" clusters of Stilbite infest this specimen. They range in size from 0.2-0.5"(0.5-1.3 cm) and have excellent form and no detectable damage. They are colored a uniform pale orange-pink, have a pearly luster, and are translucent. Accompanying them are several odd-looking apophyllite crystals- they are pseudo-cubic in form, have a dull golden color, and are very cloudy. Both the apophyllite and the Stilbite rest on a bed of drusy quartz that is composed of colorless, transparent crystals that have the standard hexagonal prismatic form and vitreous luster. This quartz druze covers several calcite crystals that are scattered around the specimen, making sparkly lumps that the apophyllite and stilbite are congregated on- very little of either mineral rests on quartz that coats the basalt base. I like specimens like this one- they show contrast both in coloration, luster, and texture.
stl-4 ($ 90.00)
Nasik, India
STILBITE specimen stl-7
$ 30.00
$ 30.00
Dims: 3.4" x 1.7" x 1.3"(8.6 x 4.3 x 3.3 cm)
Wt: 2.88 oz.(81.8 g)
Jalgaon, India
Many pale orange "wheat sheaf" clusters of Stilbte make up this specimen, along with a few large, transparent apophyllite crystals. The Stilbites range in length from 0.1 - 1.2"(0.3 3.0 cm), and have a pale orange color, a vitreous luster, and are translucent. Surprisingly enough, most of them rest on two aggregates of heulandite crystals that have a pale, rusty color, and also have a pearly luster and are translucent. The largest of the apophyllite crystals measures 1.9 x 0.8 x 0.8"(2.3 x 2.0 x 2.0 cm), and has the standard tetragonal prismatic form. Its luster is vitreous, and only its pyramidal termination is transparent, as its prism is clouded by inclusions and has many basal internal cleavage lines. The apophyllites are attached to a thin layer of basalt, and the Stilbite and heulandite are attached to the apophyllite.
stl-7 ($ 30.00)
Jalgaon, India
STILBITE specimen stl-8
$ 28.00
$ 28.00
Dims: 3.0" x 2.6" x 2.6"(7.6 x 6.6 x 6.6 cm)
Wt: 9.68 oz.(274.3 g)
Mahad, India
This specimen is mostly composed of a cluster of "wheat sheaf" aggregates of Stilbite crystals. They are large, ranging in length from 0.7 - 1.7"(1.8 - 4.3 cm), and show a large amount of damage in the form of scuffs and dents on their terminations. The cryastals have a pale pink-orange color and a pearly luster, and are translucent. They are attached to a rather small amount of basalt host rock and have several small apophyllite crystals sprinkled on them. Though this is far from being the nicest Stilbite in our selection, it is quite inexpensive for its size, and still attractive.
stl-8 ($ 28.00)
Mahad, India
STILBITE specimen stl-9
$ 50.00
$ 50.00
Dims: 3.3" x 3.3" x 2.1"(8.4 x 8.4 x 5.3 cm)
Wt: 7.18 oz.(203.6 g)
Mahad, India
A very pretty specimen, this piece consists of several "wheat sheaf" aggregates of Stilbite crystals resting on a bed of sparkling, botryoidal quartz that coats the basalt matrix. One aggregate is obviously broken and most of it is missing, but there is little other damage, and all have good form. They range in length from 0.3 - 18."(0.8 - 4.6 cm), have a pale pink-orange color and a pearly luster, and are translucent. The botryoidal quartz crust that they rest on has some elongated formations that look almost like short, stubby tentacles from a sea anemone. They are colorless in themselves and transparent, taking on the green-brown hue of the basalt base rock. It is one of the neatest zeolite specimens that we have!
stl-9 ($ 50.00)
Mahad, India
STILBITE specimen stl-10
$ 20.00
$ 20.00
Dims: 3.8" x 2.9" x 1.4" (9.6 x 7.4 x 3.6 cm)
Wt: 3.04 oz. (86.4 g)
Poona, India
A very simple specimen, this one consists of two large, orange-pink "wheat-sheaf" aggregates of Stilbite crystals that partially intersect each other at the end of a host rock covered with hundreds more tiny, white Stilbites. The two aggregates have dimensions of 1.3 x 0.6 x 0.3" (3.3 x 1.5 x 0.8 cm) and 1.3 x 0.5 x 0.3" (3.3 x 1.3 x 0.7 cm). Both have excellent form and are undamaged, and one is double-terminated, whereas the other has one termination. They have a pearly luster and are translucent. The cluster of smaller Stilbites consists of countless tiny, white-to-colorless blades that do not exceed 2 mm in length. They coat a base consisting of a druse of tiny, white quartz crystals that covers a thin crust of what appears to be thin tendrils of basalt.
stl-10 ($ 20.00)
Poona, India
STILBITE specimen stl-11
$ 30.00
$ 30.00
Dims: 3.2" x 2.5" x 2.2" (8.1 x 6.4 x 5.6 cm)
Wt: 5.85 oz. (166.0 g)
Jalgoan, India
This specimen is made up of a few dozen Stilbite crystals that coat some very large heulandite aggregates. These crystals range in length from a few millimeters to 0.8" (2.0 cm), and though some of them are rather heavily damaged, the specimen is in generally good condition. All have a very pale orange coloration, a pearly luster, and are translucent. A few tendrils of quartz-covered basalt intertwine with part of the cluster, and the heulandite makes up the specimen's "base". The heulandite aggregates have the standard diamond-shaped cross-section and pearly luster, and show noticeable damage, but are in fairly good condition.
stl-11 ($ 30.00)
Jalgoan, India
STILBITE specimen stl-12
$ 45.00
$ 45.00
Dims: 2.8" x 2.1" x 1.2" (7.1 x 5.3 x 3.0 cm)
Wt: 1.3 oz. (36.6 g)
Nasik, Maharashtra State, India
This small hand specimen consists of scores of monoclinic Stilbite blades that encrust portions of several partly intergrown stalactites. These blades range in length from 1 or 2 mm up to 1.3" (3.3 cm). Though most are too small to effectively study without magnification, the largest crystals are in excellent condition given their exposure- only one that I can see is damaged. All have very good form, with moderately well-defined edges and clean faces that possess the standard pearly luster. All have a very pale pink-orange coloration, though the smaller crystals appear to be colorless, and all are at least translucent, with a few showing patches of dim transparence.
stl-12 ($ 45.00)
Nasik, Maharashtra State, India
STILBITE specimen stl-13
$ 32.00
$ 32.00
Dims: 2.7 x 1.5 x 1.1" (6.9 x 3.8 x 2.8 cm)
Wt: 1.33 oz. (37.9 g)
Poona, Maharashtra State, India
A cluster of flattened Stilbite blades extends off of the sparse basalt base of this specimen. These Stilbites reach maximum dimensions of 0.8 x 0.6 x 0.3" (2.0 x 1.5 x 0.8 cm) and are generally in excellent condition, as only a few crystals show any damage. Their monoclinic form is excellent, with moderately well-defined edges and clean faces that possess the classic pearly luster. All have a creamy-white coloration and are translucent to dimly transparent, depending on the thickness of the blade. They are accompanied by a cluster of several apophyllites that reach lengths of 1.0" (2.5 cm) and are also in excellent condition. Their orthorhombic prismatic form is superb, with well-defined edges, clean faces, and pyramidal terminations that are truncated by small, clean basal faces. All have a pale green coloration and are transparent and moderately clear. Only a very small amount of basalt base rock is present.
stl-13 ($ 32.00)
Poona, Maharashtra State, India
STILBITE specimen stl-14
$ 28.00
$ 28.00
Dims: 4.6 x 3.0 x 2.4" (11.7 x 7.6 x 6.1 cm)
Wt: 1 lb., 2.1 oz. (514 g)
Poona, Maharashtra State, India
This hand specimen consists of several intersecting Stilbite blades that rest on a thick base. These blades measure up to 1.5" (3.8 cm) in length and are generally in very good condition, showing only a small amount of damage or breakage. All have excellent monoclinic bladed form, with relatively well-defined edges and clean faces that possess a surprisingly dull pearly luster. This dullness has likely to do with a thin coating of rust that gives them a pale orange color. There are many, much smaller Stilbite blades that rest among the bases of the larger ones, and all rest on a thick layer of calcite that coats a thin layer of the basalt host rock.
stl-14 ($ 28.00)
Poona, Maharashtra State, India
STILBITE specimen stl-15
$ 75.00
$ 75.00
Dims: 7.1 x 4.9 x 2.9" (18.0 x 12.5 x 7.4 cm)
Wt: 2 lbs., 7.3 oz. (1.115 kg)
Nasik, Maharashtra State, India
At least 10 clusters of large Stilbite crystals rests on the base of this cabinet specimen. They are in excellent condition- all are intact, and only a few show very light damage on the tips of some of their crystals. These crystals reach lengths of about 1" (2.5 cm) and widths of 0.6" (1.5 cm), and have excellent monoclinic bladed form- their edges are generally well-defined and their faces are clean, possessing a bright pearly luster. All are creamy-white in color and are translucent. They rest on a botryoidal crust that appears to be made up of countless tiny, intergrown Stilbite crystals- it is certainly not quartz or calcite. This crust coats the basalt host rock, which contains many vesicles that are filled with even more Stilbite!
stl-15 ($ 75.00)
Nasik, Maharashtra State, India
STILBITE specimen stl-16
$ 28.00
$ 28.00
Dims: 4.6 x 3.4 x 3.4" (11.7 x 8.6 x 8.6 cm)
Wt: 1 lb., 13.6 oz. (839 g)
Poona, Maharashtra State, India
Several dozen Stilbite blades rest on the botryoidal quartz host of this specimen. Most of the exposed blades are damaged and broken, but there are many that are still intact and in good condition. They achieve lengths of up to 0.9" (2.3 cm) and all have very good monoclinic form, with reasonably well-defined edges and striated but clean faces. They have a uniform creamy-white coloration with a tinge of pink and the standard pearly luster, and are translucent. Accompanying the Stilbites are many apophyllite crystals, most of which are broken. Only a few highly sheltered crystals are intact, but these have excellent form. The base rock is composed almost entirely of botryoidal and massive quartz that occurs in the form of countless intergrown nodules that do not exceed 2 mm in diameter. A small amount of the basalt host is attached.
stl-16 ($ 28.00)
Poona, Maharashtra State, India
STILBITE specimen stl-17
$ 50.00
$ 50.00
Dims: 6.1 x 5.3 x 3.2" (15.5 x 13.5 x 8.1 cm)
Wt: 3 lbs., 1.6 oz. (1.406 g)
Jalgaon, India
This cabinet specimen consists of a basalt base on which rest several large Stilbite crystals, most of which are intergrown into clusters. There is substantial damage to most of the clusters, but several crystals are intact and undamaged, including all of the single ones. They measure up to 1.6" (4 cm) in length and have excellent monoclinic bladed form, with well-defined edges and generally clean faces that possess the standard pearly luster. All are dimly translucent as individuals, though clusters are essentially opaque. They have a uniform pale "peach" color, a mixture of orange and pink, and are accompanied by hundreds of what appear to be tiny laumontite crystals.
stl-17 ($ 50.00)
Jalgaon, India
STILBITE specimen stl-18
$ 75.00
$ 75.00
Dims: 7.0 x 4.7 x 2.6" (17.8 x 11.9 x 6.6 cm)
Wt: 1 lb., 10.4 oz. (748 g)
Poona, Maharashtra State, India
Hundreds, if not thousands, of Stilbite blades extend from the agate base of this cabinet specimen. These blades are generally in very good condition- only a few around the edge of the specimen are damaged or broken- and range in length from about 1 mm to 1.5" (3.8 cm) or more. Their monoclinic form is good, and all show a pale orange-pink coloration and a pearly luster. Some appear to be slightly rust-stained. They are accompanied by several several apophyllites which are mostly buried beneath them and the agate base beneath them shows rather intense botryoidal form and is quite rust-stained.
stl-18 ($ 75.00)
Poona, Maharashtra State, India
STILBITE specimen stl-19
$ 40.00
$ 40.00
Dims: 4.9 x 4.2 x 2.4" (12.4 x 10.7 x 6.1 cm)
Wt: 1 lb., 9.1 oz. (712 g)
Poona, Maharashtra State, India
At least 10 Stilbite blades rest on the thick basalt base of this cabinet specimen. These blades are generally in very good condition and reach lengths of 1.2" (3 cm). Their monoclinic form is quite good, and all possess a pale cream coloration and the standard pearly luster. Scores of tiny, white heulandites accompany them, and small hollows in the basalt base are usually filled with either more heulandite or Stilbite.
stl-19 ($ 40.00)
Poona, Maharashtra State, India
STILBITE specimen stl-20
$ 30.00
$ 30.00
Dims: 2.5 x 2.5 x 2.0" (6.4 x 6.4 x 5.1 cm)
Wt: 4.1 oz. (115 g)
Poona, Maharashtra State, India
This hand specimen consists of a single cluster of several Stilbites. Damage is limited to a few light scuff marks on some crystals, which reach at least 1.4" (3.6 cm) in length. All have excellent monoclinic form and show a moderately deep cream coloration and the standard pearly luster. Only a very thin layer of green basalt coats its base.
stl-20 ($ 30.00)
Poona, Maharashtra State, India
STILBITE specimen stl-21
$ 25.00
$ 25.00
Dims: 3.7 x 2.2 x 1.9" (9.4 x 5.6 x 4.8 cm)
Wt: 6.2 oz. (176 g)
Poona, Maharashtra State, India
Many Stilbite blades rest on the basalt base of this large hand specimen. These blades are generally in good condition and reach lengths of 1.2" (3 cm). All have excellent monoclinic form and a pale, pink-cream coloration. Their luster is pearly and all are translucent. A thin layer of white agate separates them from the basalt base.
stl-21 ($ 25.00)
Poona, Maharashtra State, India
STILBITE specimen stl-22
$ 60.00
$ 60.00
Dims: 2.5 x 2.2 x 1.5" (6.4 x 5.5 x 3.8 cm)
Wt: 3.80 oz. (107.9 g)
Jalgaon, India
This hand specimen consists of a cluster of Stilbite "sheaves" that rests adjacent to a single, large calcite crystal. The cluster is made up of about 8 or 9 sheaves that are in excellent condition and reach dimensions of 1.3 x 0.5 x 0.4" (3.3 x 1.3 x 0.9 cm). Each sheaf is made up of many aggregated, platy crystals that have very good monoclinic form. All have a pale pink-orange color that is very faint in the smaller sheaves and a pearly luster, and are translucent. The adjacent calcite has a chubby, slightly warped form and may be twinned. It is colorless, transparent and very clear, though it contains a few internal fractures. A small basalt crust is present, and it is lined with tiny calcite platelets.
stl-22 ($ 60.00)
Jalgaon, India