so CINNAMOX -STONE. 



Realgar, forms the chief produce of the Eu- 

 genia mine, near Pola de Lena, in Asturia. 

 The vein of ore is in Carboniferous Lime- 

 stone. The tetrahedral pseudomorphous 

 crystals aftord on analj'sis, 



Mercury .... 85*12 

 Sulphur .... 11-35 



100-00 

 (See Realgar). It is also abundant in 

 China, and forms extensive mines at New 

 Ahiiaden in California, in a mountain south 

 of San Jose, between Monterey and the Bay 

 of San Francisco. 



Cinnabar is the ore from which the Mer- 

 cury of commerce is obtained, by sublima- 

 tion. The pigment vermilion is an artiticial 

 Cinnabar, which is also prepared from the 

 crude ore. 



The name is taken from the ancient Greek 

 term vxsed to denote the same substance, 

 Kivvtx.'Sa.^i • a word itself derived from Ca-^hs^ 

 heavy. The ancients derived their supplies 

 from Spain and Colchis. 

 Brit. Mus., Case 9. 



3f. P. G. Principal floor. Wall-case 23 

 (Spain), and 25 (Tuscany). 



Cinnamon-stone, Phillips. A variety of 

 ^ime-Garnet of a clear cinnamon-brown 

 tint, commonly occurring in masses which 

 are full of fissures. I'ranslucent, seldom 

 transparent. Lustre vitreo-resinous. Frac- 

 ture flat-conchoidal. H. scratches Quartz 

 with ditHculty. S.G. 3-5 to 3-6. 

 A.nalysis from Cevlon, by Gmelin : 

 Silica . . ' . . . 40-01 

 Alumina .... 23-00 

 Peroxide of iron . . . 3-67 



Lime 30-57 



Potash 0-59 



Loss by heat . . . 33 



98-17 

 BB fuses with ebullition to a darkish- 

 green glass : with borax fuses very readily 

 to a transparent glass, more or less feebly 

 coloured by iron. 



Localities. — Scotch. At the limestone 

 Quarries at Glen Gairn in Aberdeenshire. — 

 Irish. In large dodecahedral crystals of a 

 rich cinnamon colour in a coarse crystalline 

 Dolomite at Bun Beg near Gweedore ; at 

 Kilranelagh, Wicklow, &c. Foreign. — In 

 masses of considerable size in Ceylon, at 

 Malsjo in Wermland, and at St. Gotthard ; 

 also in the United States, in beautiful yel- 

 low crystals (with Idocrase) at Parsons- 

 lield, Phippsburg, and Ramford in Maine; 

 in trapezohedrons at Dixon's Quarry, Wil- 

 mington, Delaware ; crystallized and mas- 



CLAUSTHALITE. 



sive, at Amity, and on the Croton aqueduct, 

 near Yonkers, in small rounded crystals and 

 a massive variety, the latter when polished 

 forming a beautiful gem. 



Name. From its resemblance in colour to 

 the spice called cinnamon. 



When transparent and of good colour and 

 size the Cinnamon-stone from Ceylon is 

 used as a gem: most of the Hyacinths of 

 commerce are in reality Cinnamon-stones. 



Brit. Mus., Case 35. 



31. P. G. Horse-shoe Case, Nos. 903 and 

 904. 



Circle Agate. Those kinds of Agate 

 in which the stripes are arranged concen- 

 trically round a central point. 



Citrine, or Citron. A name some- 

 times given by lapidaries to limpid and 

 transparent Rock Crystal of a lemon, gol- 

 den, or Avine-yellow colour. 



Brit. Mus., Case 20. 



31. P. G. Horse-shoe Case, No, 509. 



Ci,aussenite. a variety of Hydrargy- 

 lite, from Mariana in Brazil. 



Clausthalite, Beudant. Cubical. Ge- 

 nerally occurs in masses resembling a fine 

 granular Galena, with a slight but peculiar 

 tinge of blue. Lustre metallic. Opaque. 

 Streak darker than the colour. Fracture 

 granular and shining. H. 2-5 to 3, S.G. 

 7 to 8-8. 



Conip. Selenide of lead, orPbSe = sele- 

 nium 27-6, lead 72-4 = 100; with part of the 

 lead frequently replaced by silver. 



Analysis from Clausthal, bv Stromeyer : 

 Selenium . . . " . 28-11 



Lead 70-98 



Cobalt 0-83 



99-92 

 BB on charcoal it is quickly decomposed, 

 and besidey the usual phenomena arising 

 from the presence of lead, it affoi-ds the 

 odour of decayed horse-radish, and a red- 

 dish-brown substance is deposited on the 

 charcoal. Heated over a spirit lamp in a 

 glass tube, closed at one end, the selenium al- 

 most instantly sublimes, and forms a red 

 ring within the tube, at the open end of 

 which its odour is very perceptible. On 

 heating the tube to redriess, the ore fuses 

 and the red ring partially disappears, a 

 white crj^stalline deposit remaining. 



Localities. This is a rare mineral, occur- 

 ring massive in veinsof FIsematite at Hartz- 

 gerode, in the Harz ; at Clausthal, Tilke- 

 rode, Zorge and Lehrbach ; at Reinsberg, 

 near Freiberg in Saxony ; and at the Rio 

 Tinto mines, near Seville, in Spain. 

 Brit. Mus,, Case 4. 



