PTCRANALCIME. 



Analysis : 

 Water of crystallization . 45"45 

 Sulphuric acid . . . 36-32 

 Alumina .... 12-13 

 Magnesia .... 4-68 

 Protoxide of iron and man- 

 ganese .... 0'43 



Lime 0-13 



Muriatic acid . . .0-61 

 Loss ..... 0-25 



100-00 



Entirely soluble in cold "water, forming a 

 solution whicli has an acid reaction. 



Locality. Near the port of Iquique, S. 

 Peru. 



Name. After John Pickering, President 

 of the American Academy of Sciences. 



Brit. Mus., Case 55. 



PiCRANALCiME, Meneghini. Bechi. An 

 altered form of Analcime. Occurs in tra- 

 pezohedral and cubo-trapezohedral crystals. 

 Colourless to flesh-red and colophonite-red. 

 Lustre vitreous. H. 5. S.G. 2-257. 



Comp. (Mg Na K)' 

 Analysis, by 



Silica . 



Alumina 



Magnesia 



Soda . 



Potash . 



Water . 



Si2 + 3AlSi2 + 6H. 

 iini : 



59-35 

 22-08 

 10-25 

 0-45 

 0-15 

 7-65 



99-93 

 BB fuses with difficulty. 

 Soluble in acids. 



Locality. Tuscany, covering the interior 

 of geodes in Gabbro-rosso, or the surfaces of 

 contact of Gabbro and Ophiolite ; often ac- 

 companied by Calcite, Caporcianite, and 

 Picro-Thomsonite. 



PiCROLiTE, Hausmann. A fibrous variety 

 of Serpentine, somewhat resembling As- 

 bestos. Massive, Structure radiated. Co- 

 lour leek-green, passing into yellow. Trans- 

 lucent at the edges. Streak somewhat shin- 

 ing. H. 3-5 to 4-0. 

 Analysis, from Wermeland, by Stromeyer ; 



Silica 41-66 



Peroxide of manganese . 2-25 

 Magnesia .... 37-16 

 Protoxide of iron . . . 4-05 

 Water 14-72 



99-84 

 BB with borax, affords a green glass, 

 which loses its colour on cooling. 

 Localities, The Taberg of Smaoland, in 



PICROSMINE. 285 



Sweden, in irregular veins traversing beds 

 of Magnetic Iron Ore. Wermeland ; Silesia. 



Name. From ^iy,fo;, bitter, and A/foj, stone, 



Brit. Mus., Case 25. 



PiCROPHARMACOLiTE, Stromeyer. A 

 hydrated arseniate of lime and magnesia, 

 with a large excess of magnesia : probably 

 an impure Pharmacolite. 



Comp. (CaMg)5As2 + 12H. 



Analysis : 



Arsenic acid . , . 46*97 

 Lime ..... 24-65 

 Magnesia .... 3-23 

 Oxide of cobalt . . . 0-99 

 Water 23-97 



99-81 

 Locality. Eiechelsdorf in Hesse. 

 Name. From ■xf-ceo?^ hitter^ (pa^i^Kzov, 

 poison, and A/^o?, stone. 



PiCROPHYLL, or PiKROPHYLL, Svanberg. 

 According to Breithaupt is an altered Au- 

 gite. It occurs massive and foliated-fibrous, 

 resembling Serpentine in appearance. Co- 

 lour dark greyish -green. H. 2-5. S.G. 2-75. 



Comp. (Mg Fe)3 si2 + 2H. 



Analysis, by Svanberg : 



Silica 49-80 



Alumina .... I'll 

 Magnesia .... 30-10 



Lime 0-78 



Protoxide of iron . . .6-86 

 Protoxide of manganese . trace 

 Water 9-85 



98-50 



BB infusible but becomes white ; ignited 

 with cobalt solution, assumes a dingy red 

 tint. 



locality. Sala, in Sweden. 



Name. From 5r;;sgo?, bitter, and <?^xa.ov, a 

 leaf. 



PiCROSMiNE. Ehombic : primary form a 

 right rectangular prism. Not foiAid in 

 crystals, but only massive, in granular or 

 fine columnar aggregates. Colour greenish- 

 white, or greenish-grey; sometimes dark 

 green. Translucent at the edges, or opaque. 



Fig. 333. 



Lustre -vitreous ; on cleavage - surfaces 

 pearl3^ Streak white and dull ; very sec- 

 tile. H. 2-5 to 3. S.G. 2-66. 



