schorl

Foit Jr., "Crystal chemistry of alkali-deficient schorl and tourmaline structural relationships," American Mineralogist, vol.

Other important places that have been worked recently are Antandrokomby (producing rhodizite, manandonite and beryl), Antanetinilapa (worked for gems mainly in the alluvium downhill from the pegmatite), Ampatsikahitra (producing spessartite, tourmaline and beryl) and Antokambohitra (producing poor-quality gems and schorl).

This time Paul showed me flat after fiat of good specimens, mostly thumbnail and miniature size, of olmiite from the N'Chwaning mine; goshenite beryl in sharp, lustrous, doubly terminated prisms to 2 cm with black schorl crystals, from the Erongo Mountains, Namibia; attractive pale apple-green tarbuttite in intergrown crystal sheaves partly coated by chalky white skorpionite, from the Skorpion mine, Namibia; pale brown fans of very thin, bladed crystals of eudidymite to 3 cm, from Mt.

The gorgeously sharp, gemmy, medium-blue crystals of aquamarine to 12 cm stand up at all angles from clusters of blocky, glossy black schorl crystals and chalky white, partially corroded (but still quite clean-looking) K-feldspar crystals.

The pegmatite is zoned: the contact zone consists of fine-grained microcline, dark muscovite, quartz and scarce, fine-grained schorl; the intermediate zone contains larger microcline crystals, coarse quartz, albite, gray muscovite plates and small to medium-size schorl crystals with scarce grains of green apatite.

The pegmatite is hosted in gray gneiss and consists of albite, cleavelandite, quartz, muscovite, beryl, schorl and columbite-tantalite.

Schorl Tourmaline with Spessartine Shigar Valley, Skardu, Gilgit, Pakistan 5" tall ex-collection Matthew Webb

Gemmy lime-green fluorite forms slightly rough dodecahedral crystals to 5 cm on glittering matrix composed of snowy white crests of parallel albite ("cleavelandite") crystals shot through with sleek, striated crystals of jet-black schorl; on other pieces, translucent pink apatite-(CaF) (formerly known as fluorapatite) forms lustrous tabular crystals to 7 cm, in parallel aggregates resting lightly on the same albite/schorl matrix.

The tourmaline-group mineral schorl is often written as "schorl"; Ertl (2006, and pers.

Schorl, monazite and zircon have been rarely observed in some hiddenite-bearing cavities.

(Beryl) with Schorl, 20 cm, Gilgit District, Northern Areas, Pakistan.

The scouts were able to dig around in the dump of the mine, and Marc found a small piece of schorl, which he still has today.

Columbite, beryl, schorl and uranpyrochlore are the more common minerals.

He unwrapped three nice matrix specimens, two of them aquamarine on feldspar, and the third a combination of lustrous black schorl with small aquamarines on good feldspar, all found on the steep mountainside directly above us.

Ivo Szegeny brought to Denver about 100 specimens showing fine, lustrous, translucent, trigonal "mushrooms" exceptionally to 6 cm across, some on pegmatitic matrix with crude pale green microcline crystals and black spots and microcrystals of schorl (Ivo told me that 80% of the samples of this material which are collected have dirty grayish, not pink, elbaite mushrooms, and thus never see the specimen marketplace).