TREMOLITE
Specimen tre-4

Dims: 0.7" x 0.3" x 0.2"

Wt: 9.6 g w/ specimen box

Magadi District, Kenya

This very small thumbnail specimen is basically a single broken piece of a green crystal of iron-rich Tremolite. It has a seemingly hexagonal cross-section, and its two cleavage planes are clearly visible when one looks at the cross-section. They create four complementary angles: two opposing 60-degree angles, and two opposing 120-degree angles. The material within the areas of both 60-degree angles is a paler green color than the rest of the material, due to extreme internal fracturing. The crystal shows a pearly luster and translucence. It is incomplete and heavily internally fractured. It does, however, come from Kenya, which is not a well-known locality for large crystals of this mineral.

Dims: 2.0" x 1.4" x 1.3" (5.1 x 3.6 x 3.3 cm)

Wt: 1.67 oz. (47.5 g)

Harcourt County, Otario, Canada

At least 10 slender, prismatic Tremolite crystals rest on what I think is a feldspar base. Almost all of the crystals appear to be damaged and incomplete- there may be one or two that are intact. Though none appear to have an intact termination, their prism faces represent a good triclinic prismatic form, with well-defined edges and clean faces that possess a vitreous luster. All have a pale-green coloration which seems to be the standard for individual crystals. Along with the Tremolites are 3 or 4 black epidote crystals that are in fair condition, as most are incomplete. They have the standard black coloration and vitreous luster of this material. The host rock shows some definite crystalline form, but most of its surface area is uneven and shapeless.

Dims: 3.0 x 2.1 x 1.7" (7.6 x 5.3 x 4.3 cm)

Wt: 6.40 oz. (181.5 g)

Colebrook Hill, Rosebury, Tasmania, Australia

Countless tiny Tremolite needles line the crevices and hollows of this hand specimen. These needles to not generally exceed 0.2" (5 mm) in length but are in very good condition due to the protective nature of their surroundings. They are too small for me to effectively study their form, but likely have good monoclinic form. All have a dull, gray-green coloration and a pearly luster- when clustered together, their luster reminds me a little of velour or crushed velvet. The Tremolite is visibly compact in a few areas, too, and is accompanied on the piece by several small ferroaxinite crystals, many of which are exposed and damaged. Their triclinic form is good, though, and all show a dark brown color and a bright, vitreous luster. A small amount of crystalline quartz is also present. The base rock appears to be made up mostly of massive Tremolite, but there are bits of broken Axinites within, along with a small amount of a metallic sulfide.

Dims: 5.0 x 4.4 x 2.1" (12.7 x 11.2 x 5.2 cm)

Wt: 1 lb., 2.3 oz. (519 g)

Gumeracha, Southern Australia

This large cabinet specimen consists of a chunk of almost bladed, compact Tremolite. The material shows definite crystalline characteristics, but no actual crystals can be isolated. It has a pale, creamy color over most of its area, but some portions appear to be rust-stained. These stained areas are likely weathered and show a dull luster, whereas those which are freshly exposed possess a bright, pearly luster. There is no base or host material present.

Dims: 2.6 x 2.6 x 1.0" (6.6 x 6.5 x 2.5 cm)

Wt: 6.1 oz. (174 g)

Canaan, Connecticut, U.S.A.

This hand specimen consists of a partly-exposed, fan-like Tremolite aggregate that extends through a granular calcite matrix. This agggregate has dimensions of 2.5 x 2.3 x 0.1" (6.4 x 5.9 x 0.3 cm) and is in fair condition, as it shows considerable breakage along its exposed edges. Though tightly aggregated, it is obviously crystalline and has a white color and an almost silky luster. If exposed, the aggregate would likely be translucent. Canaan, Connecticut is considered one of the better-known U.S. localities for this mineral.

Dims: 2.4 x 0.9 x 0.7" (6.1 x 2.3 x 1.8 cm)

Wt: 22 g

Brumado Mine, Bahia, Brazil

Several intersecting Tremolite sprays make up this hand specimen. These sprays contain Tremolite needles that are generally in good condition and reach lengths of 1.9" (4.9 cm). They are too compact for effective study, but likely have reasonably good monoclinic form. Their color is a dull gray-white and their luster is silky. There is no host rock present.