MINE R 



Orjrct.igno- Geogiuuiic and Geographic Situations. Occurs in 

 y- primitive, transition, secondary, and alluvial rocks in 

 *~~~:~~* most countries of Europe. 



t. The principal use of this mineral is for gun- 



. for which purpose it is excellently fitted, on ac- 



:t of its hardness, the abundance of sparks it affords 



with steel, and the sharp fragments it gives in break. 



ing. 



ELEVENTH SUBSPF 

 .dooy. CALCEDONY, Jameson. Kalzedon, Werner. 



Four kind', viz. Common Calcedony, Chrysoprase, 

 Plasma, and Camelian. 



:\<nd COMMON CALCEDONY, /BIOM. Geroei- 

 ner Kalzedon, Werner. 



F.xterr.al Character*. Colours grey, yellow, brown, 

 blue, green, and black. Occurs in lamellar, and also 

 in fibrous distinct concretions. Internally dull ; the 

 fplintery varieties exhibit a faint degree of lustre. 

 Fracture even, which sometimes passes into imperfect 

 conchoidal, and splintery. Generally semi-transpa- 

 rent ; but the black and white varieties are only trans- 

 lucent. 



drognottic Situation. Occurs in primitive, second- 

 ary, and alluvial rocks, in balls, kidneys, angular pieces, 

 short and thick beds, veins, and rolled pieces. 



Geographic .Situation. It is frequent in most of the 

 districts in Scotland, and also in fimilar tracts on 

 the continents of Europe, Asia, Africa, and America. 



t. As it is hard, susceptible of a fine polish, and 

 exhibits beautiful colours, and considerable transparen- 



ALOGY. 



547 



Chryso- "'id Kind CIIBYSOPBASE, Jameton. Krisopras, 



cy, it is employed as an article of jewellery. 



E, Ju 

 Werner. 



crnal Charaders. Characteristic colour apple- 

 green, and greenish-grey. Occurs generally massive, 

 and sometimes in plates. Internally doll, seldom glim- 

 mering. Fracture even. Translucent, inclining to 

 tctn i-tran spa rent. 



jnoitic and Geographic Situations. It occurs in 

 plates and cotemporaneous veins, in primitive serpen- 

 tine in Silesia. 



'. It is considered as a gem, and is cut into ring- 

 stones, necklaces, bracelet*, ear-drops, and brooches. 

 Plasma. Third Kind. PLASMA, Jameson. Plasma, Werner. 



rr.nl Cfiirac'crt. Colour gras-green. Inter- 

 nally lustre glistening, inclining to glimmering. Frac- 

 ture imperfect, and rather flnt conchoidal. Translu- 

 cent, inclining to semi-transparent. 



r;nottic and Crogrtr. tiont. It occur> in 



-. associated wi Mmtot'thc 



specimens in cabinets have been collected among the 

 ruins of Rome. 



f '*f- It was considered by the Romans as a gem, 

 and was cut into ornaments ; and frequently figures 



<!> Arrived upon it. 



CmrnelUn. Jouiih Kind. -.CABXELIAX, Jameson. Cameol, Wer. 

 External Characters. Colours red, brown, yellow, 

 n, and white. Occurs massive, and in fibrous la- 

 mellar concretions. Fracture perfect conchoic' 

 :n the reniform varieties. Lustre glisti 

 - passing into hhinine, and vitreous. Gene- 

 rally semi-transparent ; seldom translucent. 



gnostic ai > ,' ic X'lualions. It frequently 



occurs as a constituent j-art of agate, and in general 

 has the same geognostic situation as common calcedony. 

 The secondary trnp-rocks so abundant in Scotland often 

 contain carnelian, either alone, or in agate. The mo*t 

 beautiful carnelians are brought to this country from 

 Arabi, India, Surinam, Siberia, and Srrdinia. 



1 * 'It is cut into'seal-stoncs, ring-stones, brace. 



lets, necklaces, brooches, and crosses ; and figures are Oryctogno. 

 often engraved on it. sy. 



TWELFTH SUBSPECIES. v - - ^-y-*^ 



HELIOTROPE, Jameson. Heliotrop, Werner. Heliotrope. 



External Characters. Colour Green, with red and 

 yellow spots. Occurs massive. Internal lustre glisten- 

 ing, and resinous. Fracture conchoidal. Generally 

 translucent on the edges ; seme varieties translucent. 



'ic and Geographic Situations. It is found 

 in rocks belonging to the secondary trap- formation, in 

 Siberia, Tartary, Iceland, and even in Scotland. 



Utct.lt is cut and polished, and worn as an orna- 

 mental stone. 



THIRTEENTH SUBSPECIES. 



JASIEU. Jasper. 



Five kinds, viz. Egyptian Jasj>er, Striped Jasper. 

 Porcelain Jasper, Common Jasper, and Agate Jasper. 



Pint Kind. EGYPTIAN JAM-ER, Jameson. Brainier Egyptian 

 Egyptischer Jaspis, Werner. Jasper. 



mid Characters. Colours brown, yellow, and 

 grey, frequently disposed in concentric stripes, alter, 

 nating with black stripes. In the brown colour there 

 sometimes occur black .-pots, and similar coloured den. 

 dritic delineations. Internally partly glistening, partly 

 glimmering. Fracture conchoidal. Very feebly trans, 

 lucent on the edges, or almost opaque. 



Geognoslic and Geographic Situations. It occurs 

 loose in the sands of the desert, and in conglomerate 

 rocks in Egypt. 



It it, cut and worn as an ornamental stone. Striped 



</ Kind STIiirtl) JASI-EO, Jameson. Band Jasper. 



-, Werner. 



>nul Characters. Colours grey, green, yellow, 

 and red, and seldom blue. There are always several 

 colours together, and these are arranged in striped 

 and flamed, and sometimes in spotted delineations. 

 Occurs massive. Internally dull. Fracture conchoidal. 

 Opaque, or very feebly translucent on the edges. 



ic and Geographic Situations. It occurs in 

 secondary clay-porphyry in the Pentland Hills near 

 Edinburgh ; but the most beautiful varieties are found 

 in Siberia. 



L'sf. This mineral receives an excellent polish, and 

 hence is used like agate for ornamental purposes. 



Third Kind PORCELAIN-JASPER, Jameson. Por. Porcelain, 

 zellan Jaspis, Werner. Japr. 



External Characters. Colours grey, blue, jellow, 

 and seldom black and red. Occurs most commonly, 

 massive, and is frequently cracked in all directions. 

 Internally glistening, sometimes approaching to shin- 

 ing, sometimes to glimmering, and even to dull ; and 

 the lustre vitreo-resinous. Fracture conchoidal. Opaque. 

 (Jeognottic and (re graphic Situations. It occurs 

 along with pseudo-volcanic rocks in Fifeshire ; near 

 Dudley in Warwickshire, and in many other parts of 

 Europe and America. 



Fourth Kind. COMMON JASPEH, Jameson. Gemeiner Common 

 Jaspis, Werner. Jasper. 



l-'.j I crnal Characters. Colours red, brown, and black. 

 Occurs massive. Internally varies from shining to 

 dull ; and lustre resino- vitreous. Fracture of some 

 varieties is more or less perfect and flat conchoidal, and 

 those have a shining or glistening lustre ; in others it 

 is even, with a glimmering lustre, or fine earthy and 

 dull. Opaque, or \ery faintly translucent on the edges. 



Gcognoilic an ' '</< Stttialicns. It occurs in 



veins and imbedded masses in primitive, transition, and 

 secondary rocks in Scotland, England and Ireland. It 

 is not unfrcqucnt on the continents of Europe, Asia, 

 Africa, and America. 



