540 



MINEKALOGY. 



Orjctogno- 

 sy. 



Atbestus. 

 Rock-cork. 



Amian- 

 thus. 



Common 

 Asbestiif. 



Rock, 

 wood. 



FIFTH SUBSPECIES. 



ASBEBTUS, Jameson. Asbest, Werner, 



This subspecies is divided into four kinds, viz. Rock- 

 Cork, Amianthus, Common Asbestus, and Rock-wood. 



First Kind. RocK.-CoRK.,Jameson. Berg Cork, Werner. 



External Characters. Colours white, grey, and yel- 

 low. Occurs massive, in plates that vary in thickness, 

 corroded, and with impressions ; and these forms are 

 composed of delicateand promiscuous fibrousconcretions. 

 Internally feebly glimmering, or dull. Fracture fine 

 grained uneven, inclining to slaty in the large. Opaque. 

 Very soft. Becomes shining in the streak. Sectile, al- 

 most like common cork. Slightly elastic flexible. Dif- 

 ficultly frangible. Adheres slightly to the tongue. 

 Emits a grating sound when we handle it. Feels mea- 

 gre. So light as to swim on water. Specific gravity, 

 0.679, 0.991, Brisson. 0991, Haiiy. 



Chemical Characters. It melts with great difficulty 

 before the blowpipe into a milk-white nearly translu- 

 cent glass. 



Geognostic Situation. It occurs in cotemporaneous 

 Veins in serpentine, and in red sandstone ; also in me- 

 talliferous veins in primitive and transition rocks ; and 

 occasionally in mineral beds. 



Geographic Situation. It occurs in veins in the ser. 

 pentine of Portsoy, and in the red sandstone of Kin. 

 cardineshire ; in plates, in the lead-veins at Lead Hills 

 and Wanlockhead in Lanarkshire; and in small quan- 

 tities at Kildrummie in Aberdeenshire. 



Second Kind. AMIANTHUS, or FLEXIBLE ASBESTUS, 

 Jameson. Amiant, Werner. 



External Charact/ rs. Colours white, grey, blue, and 

 green. Sometimes blood-red, particularly when it occurs 

 in veins in serpentine. Occurs in fibrous distinct concre- 

 tions. Internally lustre shining and pearly. Translucent 

 on the edges, or opaque. Very soft. Perfectly flexible. 

 Geognostic Situation. It occurs frequently along 

 with common asbestus, in cotemporaneous veins in ser 

 pentine. 



Geographic Situation. It occurs in serpentine in the 

 islands of Mainland, Unst, and Fetlar in Shetland ; and 

 in the same rock at Portsoy. 



Uses.^-Thia mineral, on account of its flexibility, 

 and its resisting the action of considerable degrees of 

 heat, was woven into those incombustible cloths in 

 which the ancients sometimes wrapped the bodies of 

 persons of distinction, before they were placed on the 

 funeral-pile, that their ashes might be collected free 

 from admixture. 



Third Kind. COMMON ASBESTUS, Jameson. Ge- 

 meiner Asbest, Werner. 



External Characters. Colours dark leek-green, and 

 mountain-green ; also greenish-grey and yellowish- 

 grey. Occurs massive ; and in fibrous distinct con- 

 cretions. Internally glistening and pearly. Fracture 

 not visible. Translucent, or only translucent on the 

 edges. Soft, approaching to very soft. Rigid or in- 

 flexible. Rather brittle. Difficultly frangible. Feels 

 rather greasy. Specific gravity, 2.000, Karsten. 2.542, 

 Kirwan 2.591, Breilhaupt. 



Geognosiic Situation. Like amianthus, it occurs in 

 veins in serpentine, and in primitive greenstone. 



Geographic Situation. It occurs in the serpentine 

 of Shetland, Long Island,, Portsoy, Anglesey, and Corn- 

 wall 



Fourth Kind. Rocic-Wooo, or LIGNEOUS ASEESTUS, 

 Jameson Bergholz, Werner. 



External Characters. Colour wood-brown, of various 

 degrees of intensity. Occurs massive, and in plates ; 

 also in delicate and promiscuous fibrous concretions. 

 Internally lustre glimmering. Fracture curved slaty. 

 Becomes shining in the streak. Soft, passing into very 



soft. Opaque. Sectile. Specific gravity, before im- Oryttogno- 

 mersion, 1.534 ; after immersion, 2.225, Brdthaupt. \v. 



I. -1_'L1_L_I il__l1 



ChcmtcalCharactrs,\i> infusiblebefore theblowpipe. 

 Geognostic and Geographic Situations. It occurs at 

 Sterzingin the Tyrol, in primitive rocks. 



3. PIUSMATOIDAL AUGITE, Jamcsott. Prismatoidis- Primatoi. 

 cher, Augit, Mohs. dal Augite. 



Prism=114 37'. Cleavage sometimes prismatoidal. 

 Hardness=:60.70. Specific gravity=3.2, 3.5. 



This species contains two subspecies, viz. Epidote 

 and Zoisite. 



FIRST SUBSPECIES. 



EPIDOTE or PISTACITE, Jameson. Epidote, Haiiy. Epidote. 

 Pistazit, Werner. 



External Characters. _ Colours green and black. Oc- 

 curs massive ; also in distinct concretions, which are 

 granular and fibrous, which latter are collected into 

 wedge-shaped prismatic concretions. Frequently crys- 

 tallized in oblique four-sided, and also in six-sided 

 prisms. Externally the lustre alternates from splendent 

 to glistening, and is vitreous; internally it is shining or 

 glistening, and is resinous, inclining to pearly. Frac- 

 ture conchoid?.!, sometimes uneven, sometimes even or 

 splintery. Alternates from translucent to translucent 

 on the edges, and to nearly transparent. 



Chemical Characters. Before the blowpipe it is con- 

 verted into a brown-coloured scoria, which blackens by 

 continuance of the heat. 



Epidote from the Valais. 



Constituent Paris. Silica . 37.0 



Alumina . 26'.0 



Lime . 20.0 



Oxide of iron 13'0 



Oxide of manganese 0.6 

 Water . 1.8 



Loss . 1.0tOO.O 



Geognostic Situation. Occurs in beds and veins, and 

 sometimes as an accidental constituent part of rocks. 



Geographic Situation. In Arran it occurs in syenite 

 and clay-slate ; in Mainland in Shetland in syenite, and 

 in other districts in Scotland. 



SECOND SUBSPECIES. 

 ZOISITE, Jameson. 

 This subspecies is divided into two kinds, viz. Com- 

 mon Zoisite and Friable Zoisite. 

 First Kind. COMMON ZOISITE, Jameson. Zoisite, Werner. Common 



External Characters __ Colour grey. Occurs massive ; Zoisite. 

 also in large prismatic distinct concretions. Internal- 

 ly it is shining on the cleavage, and glistening, on the 

 fracture surface, and the lustre is resino-pearly. Frac- 

 ture small- grained uneven. Feebly translucent, or only 

 translucent on the edges. 



Geognoslic and Geographic Situations. It was first 

 observed in the SauaTp in Carinthia ; and we have it 

 from Glen Elg in Inverness- shire, and from Shetland. 



Second KzW.- FRIABLE ZOISITE, Jameson. Miirber Friable 

 Zoisit, Karsten. 



External Characters Colour reddish-white, which 

 is spotted with pale peach-blossom red. Massive, and 

 in very fine loosely aggregated granular concretions. 

 Very feebly glimmering. Fracture intermediate be- 

 tween earthy and splintery. Translucent on the edges. 

 Geognoslic and Geographic Situations. It occurs im- 

 bedded in green talk at Radelgraben in Carinthia. 



4. PRISMATIC AUGITE, or TABULAR SPAU, Jameson. Prismatic 

 Prismatischer Augitspath. Mohs. Schaalstein, Werner. 

 Tafelspath, Karsten. 



Pri$Hi= 105. Cleavage indeterminate diagonal. Hard- 

 ness=4.5 5.0. Sp. gr.=2.7 2-9. 



Ex'emalCharactcrs. Colour white. Occurs massive, 

 and coar.->ely disseminated ; also in granular and lamel- 

 lar distinct concretions. Internally the lustre varies 



Zoisite> 



