THE MINERAL ILVAITE

Dims: 1-1/8" x 3/4" x 5/8"

Wt: 15.3 g

Dalnegorsk, Siberia, Russia

Though the faces of this excellent little Ilvaite crystal are not the cleanest, it's not due to damage! Each of the 4 prism and 2 termination faces show heavy growth patterning as well as many minute crystals growing off their larger relative. The crystals are all black and opaque. The main crystal is double-terminated, with one of the terminations being damaged(it's where the crystal was attached to the host rock). This is rather uncommon, I believe, and certainly of exceptional quality.

Dims: 0.8 x 0.8 x 0.6" (2.0 x 2.0 x 1.5 cm)

Wt: 19.0 g w/ specimen box

Dal'negorsk, Primorskiy Kray, Russia

This thumbnail specimen consists of 3 partly intergrown Ilvaite crystals. These crystals range in size from 0.4 x 0.2 x 0.2" (1.0 x 0.5 x 0.5 cm) to 0.9 x 0.7 x 0.6" (2.3 x 1.8 x 1.5 cm) and are in excellent condition, showing only one spot of damage where a small crystal broke off at its base. The mid-sized crystal is particularly interesting, as it grows off of the largest crystal at almost a right angle. All have excellent orthorhombic prismatic form, with edges and faces that appear to be somewhat disseminated, but are nontheless quite defined. Their color is black with subtle brown highlights, their luster is bright and almost adamantine, and they are opaque. There is no host rock present, and the specimen is hot-glued into a square plastic specimen box.

Dims:4.0x2.8x1.7" (10.1x7.1x4.3 cm)

Wt: 12.3oz. (350g)

Dal'Negorsk, Primorskiy Kray, Russia

This is a complex specimen. A thin layer of massive manganocalcite rest upon a matrix of long, fibrous hedenburgite crystals. Scattered over the manganocalcite are quartz, scalenohedral calcite, and ilvaite crystals. The largest ilvaite crystal measures 0.7" (1.8cm) in length. Finally, all of these minerals are covered with a layer of microcrystalline ilvaite. Some of the larger ilvaites are exposed so that the striated prism faces may be observed. There is only minor damage near the edges of this specimen.

Dims:1.5x1.1x0.6" (3.8x2.8x1.5 cm)

Wt: 0.8oz. (22g)

Lvl 5, Los Remedios Mine, Taxco, Guerrero, Mexico

This specimen consists of a thick crust of ilvaite crystals with no matrix material. These crystals are black and lustrous, displaying the vertical striations typical to this species. Some of the crystals have an earthy brownish-black coating of ilvaite on one side. The only damage to this specimen is on the edges, and this is very minor.

Dims:2.0x1.5x1.4" (5.1x3.8x3.6 cm)

Wt: 2.9oz. (83g)

Lvl 5, Los Remedios Mine, Taxco, Guerrero, Mexico

A thick crust of brilliant, black, sparkling ilvaite crystals rests on a matrix of massive ilvaite in this specimen. The crystals exhibit the characteristic diamond-shaped cross section and vertical striations found in this species. For a black, opaque mineral, this is incredibly aesthetic. There is only minor damage on the edges of this specimen where it was pried from the host rock.

Dims: 3.18x2.58x1.22" (8.08x6.56x3.09cm)

Wt: 4.25oz (120.3g)

Dalnyegorsk, Russia

This specimen contains dozens of fine ilvaite crystals. They are black, opaque, and to my eye, they have more of a vitreous luster than the usual sub-metallic luster. Many of the crystals have a classic diamond shape, but many others are distorted, especially in that the crystals are curved. The faces generally show striations, and there is very little damage except around the edges of the specimen.

Dims: 2.20x1.81x1.33" (5.58x4.58x3.37cm)

Wt: 3.90oz (110.4g)

Dalnegorsk, Russia

This is a specimen of nearly pure ilvaite. It has a shiny black color and an opaque submetallic luster, and the crystals individually have a distorted square cross section, and rough slanted terminations. An unusual aspect is that the crystals are nearly parallel at the base but then curve slightly outward towards the tips. Also, the crystals (while nearly parallel) have random orientations. There is a tiny amount of a dull white mineral present.

Dims: 2.62x1.24x0.79" (6.65x3.16x2.00cm)

Wt: 1.91oz (54.0g)

Dalnyegorsk, Russia

This specimen has five black ilvaite crystals on a white granular matrix. The ilvaite crystals are well formed, opaque, and have a vitreous luster, although the largest crystal is somewhat distorted in cross-section and is missing one side, due to a growth of tiny silvery-gray crystals (it just looks like a dull gray mineral to the unaided eye). I do not know what this mineral might be, although it has an appealing appearance under a high power loupe, having tiny flat circular crystals with a silky luster. The white matrix is also somewhat of an identification challenge. First of all, most of it is a loose, even crumbly assemblage of tiny transparent colorless crystals (which are too small for me to determine their form even with a loupe). Some of the crystals are long and prismatic, and these appear to have a hexagonal cross section, and while I don't see good terminations, there are some broken crystals that look like they may exhibit a conchoidal fracture. This leads me to believe that they are quartz (an easy default guess in any case), however the long crystals are very long and thin for quartz, and the granular matrix that easily comes off on your fingers feels too soft. Overall, the white matrix is translucent enough that I am certain no additional ilvaite crystals are buried inside.