SPHENE
Specimen spe-7
$ 36.00Dims: 1.4" x 0.4" x 0.3" (3.6 x 1.0 x 0.8 cm)
Wt: 2.4 g
Thormale, Nala, Pakistan
This rather simple specimen consists of 3 intergrown Sphene crystals. The 2 larger crystals have a flat, elliptical, bladed form and show evidence of twinning, while the smaller crystal has an oblong, rhombohedral prismatic form. The largest crystal measures 1.4 x 0.3 x 0.2" (3.6 x 0.8 x 0.5). The cluster is partially covered with tiny crystals that I think are made of either more Sphene or possibly chlorite; these crystals provide heavy interference, making it difficult to see any transparence or even translucence, and in turn, the crystals' coloration, and spoiling their adamantine luster. However, one end of the larger crystal has a much lower concentration of these tiny crystals, so one can easily see the olive-green color and bright luster. The crystal's transparence is also visible, as are the many inclusions and internal fractures that spoil its clarity. I like it because it shows well what such a coating of small crystals can do to alter many aspects of its appearance.