147 
EARTHS. SILICEOUS. 42. Gemma. 
^’’onutus. 
Hyacinthns Gemma. Cronst. miner. 69. A. 2. 0. 
G^ma Granites. Wall. fyft. min. I . f . 2 J 3 - 4 - ^ ■ 
Found in Swazerlan^, ^ ™ r“ „ of 
of S( 7 -«Va, in Brafd and C«y/w, fometimes in the form ot 
rounded grains mixed with fand or earth, 
ded in other ftones, in 6.fided lofes S 
by a a-fided pyramid : is twice as hard as fpar, and lolcs its 
colour u hen fprinkled with the ftrongcr mineral acids. 
Hard, ponderous red, of unequal texture, preferving its 
colour in a low heat, melting in a ftronger heat into a 
brown opake fpumid mafs. 
Borax tcll’cllatus. iVf- »<3/. xii. J-/ 72. n. J* 
Gemma plus minus pellucida. Wall. min. ii/* 
Grarnet. Carbuncle. Ktrnuan mineral, i./. 258. 
Gtrnit. Schmeffe’- mineral. 1. p.ixj- 
Garnet. Thomjon chem. 3 'P-^l^' 
Silex Granatus. Sowerby Brit, min, /-43, 44 * 
1. Pellucid. 
Granat. cryftal. pellucid. WaU.fyft^ i* p- “' 4 ' 
2. Opake. 
Granat. cryftal. opac. Wall. fvt.\. p- 2^3. n. 3. 
Borax margodes. iyir. nat.XA. 
3 Breaking into granular fragtper.ts, 
Grarat,fig. indeterm. Wall, fyft, i. /*• 25°* "• *• 
Granat. panic, granulat. Cronst. miner. 69. A. 1. 
4. Breaking into cruftofe fragments. 
Granat, fig, indeterm. Wall. fft. \.p. 251. ». 2. 
5. Of a common form. 
6. In the form of loofe rounded grains with the angles worn oft, 
and found in rivers, the common foil, and among fand. 
7. In the form ofcfyftals, and generally inibedded in « matrix, 
light. . 
a. In double 4-fided pyramids. 
With the tips truncate. 
Gmel. Jyst. not, 3. p. 447 * *• 
b. In double 8-fided pyramids, , . -j 
Each fide augmented by another 4-fided depreffed pyramid. 
/Imoen acad. l. />. 482. _ , r. j u r 
e. In 3-fided pyramids, with the margins of the fides and bale 
truncate. 
Gmel. fyst. not, 3. p. 447. t. l.f. 37. . , , ^ 
d. In 6.lided pyramids, with the margins of thebafe truncate. 
(^mel.Jyst.nnt. 3. p. 445, 2. I, A 2. 
T 2 
