PHENAKITE
Specimen phe-4

Dims: 0.6 x 0.3 x 0.3" (1.4 x 0.9 x 0.9 cm)

Wt: 2 g

Mount Antero, Chaffee County, Colorado, U.S.A.

This small thumbnail specimen consists of a single, doubly-terminated Phenakite crystal that is in excellent condition. Its trigonal form is quite good, and shows interpenetration twinning much like that of cinnabar crystals. It is colorless, transparent and moderately clear and has a pearly-to-vitreous luster. Portions of a few tiny crystals erupt from some spots, but these do not amount to more than a few faces. A dusty black material coats small areas on the crystal, but there is no host rock present.

Dims: 1.1 x 0.7 x 0.6" (2.8 x 1.7 x 1.6 cm)

Wt: 7 g

Mount Antero, Chaffee County, Colorado, U.S.A.

Dozens of tiny Phenakite prisms rest on the crystalline muscovite base of this thumbnail piece. The largest of these crystals is 0.3" (8 mm) long and is the easiest to study- it is in excellent condition and has excellent double-terminated trigonal form. Like the others, it is colorless, transparent, clear, and has a vitreous luster. The muscovite base on which the Joaquinites rest is made up of many well-formed, intersecting platelets.

Dims: 0.8 x 0.5 x 0.4" (2.0 x 1.3 x 1.0 cm)

Wt: 3 g

Mount Antero, Chaffee County, Colorado, U.S.A.

This thumbnail specimen consists of a cluster of at least 6 intergrown Phenakite crystals that are in very good condition and reach dimensions of 0.5 x 0.4 x 0.3" (1.2 x 1.0 x 0.7 cm). The largest crystal shows a small spot of damage, but the rest are in excellen shape. All have excellent trigonal prismatic form and are colorless and transparent. They contain many cloudy inclusions, however, and possess a rather dull, pearly-to-greasy luster. A few broken muscovite blades are attached to the cluster, but no other material is present.

Dims: 1.2 x 1.0 x 0.8" (3.0 x 2.5 x 2.0 cm)

Wt: 16 g w/ foam base

Malyshevo Mine, Ekaterinberg, middle Urals, Russia

A single Phenakite crystal rests in the dark, micaceous matrix of this thumbnail piece. The crystal has dimensions of 0.6 x 0.5 x 0.4" (1.5 x 1.3 x 1.0 cm) and is in very good condition, showing almost no damage. Its trigonal prismatic form is somewhat flattened along one axis, but is still well-defined. Its pale yellow color and pearly luster are common for the specie, and it is transparent and moderately clear. The piece is hot-glued to a foam base which fits into a plastic thumbnail box.

Dims: 1.2 x 1.1 x 1.0" (3.0 x 2.8 x 2.5 cm)

Wt: 22 g

Mount Antero, Chaffee County, Colorado, U.S.A.

This thumbnail specimen consists of a few Phenakite crystals, some of which are intersecting, that are scattered through a crystalline muscovite matrix. Most of the crystals are broken or at least lightly damaged, including the largest. This particular crystal measures about 0.6 or 0.7" (1.5 - 1.8 cm) in diameter and is incomplete due to its intersection with another crystal that was since removed. Its trigonal form has a nearly pseudo-dodecahedral appearance and is very well-defined. All are colorless, transparent and dimly to moderately clear, containing many cloudy inclusions. Their faces have a luster that ranges from nearly matte to vitreous. Only a few other, tiny crystals are sufficiently intact to show good form. The surrounding matrix consists of scores of tiny, pseudohexagonal muscovite books that are intergrown.

Dims: 0.75x0.39x0.39" (1.9x1.0x1.0cm)

Wt: 21.20ct (4.24g)

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This phenakite crystal has an excellent hexagonal shape, with a pyramid termination. There is only a small amount of damage to the tip and several edges. While the phenakite is transparent and nearly colorless (but with a hint of yellow), it has inclusions, or more properly intergrowth with a mineral that is opaque, dull, and has a pink cast.

Dims: 1.09x1.07x0.69" (2.77x2.72x1.75cm)

Wt: 0.67oz (19.0g)

Malyshevo mine, Ural, Russia

This is a single crystal of phenakite, a beryllium silicate mineral. It is roughly hexagonal in shape, with roof shaped edges. It is incomplete, showing only 6 (of a possible 14) faces. It is colorless and transparent, with a rough exterior that makes it difficult to see into the interior, except at a few spots where fractures expose a somewhat vitreous surface. Also, parts of the surface are coated with a thin layer of muscovite crystals.