MINERALOGY fracture conchoidal and splintery. C.c. : silica 49 8, lime 43 5, protoxide of manganese 2 3, protoxide of iron 2 9, water 37. Kilfiuiclieu and Torosay (Mull), Xonotla (Mexico). 601. TOBEUMORITE, 3(0a 4 , H)Si 6 + 2jSF. Massive, fine granular; translucent; fracture hackly. H. 5; G. -=2 4. Pale pink. C.c.: silica 49 8, lime 37 2, water 12 9. Tobermory (Mull), Dunvegan (Skye). 602. OKENITE, CaHSLj + H. Right prismatic. ooP 122 19 . Usually fine fibrous; radiating. H. -=5; G. =2 28 to 2 36. Pellucid; slightly pearly. Yellowish to bluish white. In powder easily sol. in h. acid, leaving gelatinous flakes after ignition. C.c.: 56 6 Bilica, 28 4 lime, and 17 water; an apophyllite without the fluorine. Disco Island, Faroes, and Iceland. 603. APOPHYLLITE, 8(CaSi + 2H) + KF . Pyramidal. P 120 56 . P, oopoo (m), OP (o), ooP2 (r). Ilurely lamellar. Cl. o, perfect. Brittle. H. =4 5 to 5; G. =2 3to 3 4. Transparent; vitreous. On o pearly (Ichthyoph- thalmitc). Colourless, rarely pink, green, red, brown, and yellow. B.B. exfoliates, intumesces, and melts to white enamel. Sol. in h. acid, leaving silica. C.c.: silica 50 3, lime 247, water 15 9, Fig. 542. Fig. 544. potassium 4 3, fluorine 2 1. Dunvegan and Storr, Skye (fig. 544); Chapel, Fife ; Corstorphine (fig. 542) and Ratho, near Edinburgh ; Kilsyth, Bowling, Kilpatrick ; Port Rush, Ireland. In the form P (fig. 79), grass-green at Oxhaveer, Iceland (Oxhavccrite) ; Uto, Sweden; Andreasberg and Faroes (pink) ; Faroes, and Poonah in India (green). Internal structure tesselated, being built up of wedge and lenticular forms with varying refractive indices, hence exhibit ing a beautiful structure with polarized light. 604 . G YROLITE, (f Ca -I- jfi)Si + H . Lamellar, radiate, spherical, and investing. H. =3 to 4. Pearly. Bluish white to cream-coloured. Transparent, rapidly becoming opaque. C.c.: silica 53 3, lime 32 9, water 13 8. Quiraing, Lyndale, and Storr, Skye ; Loch Screden and Carsaig, Mull ; Canna ; Karartut, Niakornak, and Disco ; Faroes ; Nova Scotia. 605. ANALCIME, AlSi 3 -f NaS i + 2& . Cubic. ooQoo ; 2O2. Fracture uneven. H. - 5 5 ; G. - 2 1 to 2 "28. Colourless, white, flesh-red, scar let. Vitreous; transparent. B.B. melts without frothing to a clear vesicular glass. Decomposable with gelatinization in h. acid. C.c. : 54 - 5 silica, 23 3 alumina, 14 1 soda, 8 2 water. Walls, Orkney ; Talisker, Skye; Sanda, and Hebrides generally. Trans parent at Eigg, and Elie, Fife scarlet at Bowdens, Kincardine; opaque white at Glen Farg, Salisbury Crags, and Dumbarton; Giant s Causeway, Seisser Alp in Fig. 545. Tyrol, Cyclopean Islands (fig. 545), Faroes, Iceland, and Nova Scotia. EudnopMte is a variety. Pecto- lite (sp. 598) occurs pseudomorphous after analcime, in large crystals of a, n, at Ratho, Ediuburghshire. 606. POLLUX, 3( AlSi 3 + (sf , Na)Si) + 23. Cubic. ooOoo ; 202 (fig. 546). Also massive. Gum-like externally. Brittle, with traces of cleavage. Fracture con choidal. H. -5-5 to 6-5; G. = 2 86 to 2 9. Colourless. Vitreous. Sol. in n. . ,..,, acid. C.c. : silica 44, alumina 16, oxide Fl & 546 (S P 606) of caesium 34, soda 2 5, water 2 4. Elba. The only mineral which contains caesium in quantity. 421 607. FAUJASITE, Cubic ; in octahedrons with the icositetrahedron |0|. Fracture uneven; brittle. H. = 7 ; G. -1 92. Transparent; vitreous to adamantine. White to brown. Sol. in h. acid. C.c. : 46 8 silica, 16 alumina, 4 4 lime, 4 8 soda, 28 water. Kaiserstuhl in Baden, Annerod near Giessen, Eisenach, Marburg. 608. CHABASITE (Lime-Chatasite), AlSi 3 + CaS i + 6H . Rhombohedral ; R 94 46. ^R ; - $R (r) ; - 2R () ; ooP2 (a). Twins very common (generally interesting), on faces >P and Fig. 547. Fig. 548. PGO . Primary rhombohedron is sometimes twinned with a crystal with faces r, e, s. Cl. r perfect. H. - 4 to 4 5 ; G. - 2 to 2 2. Transparent or translucent; vitreous. Colourless, and brownish, Fig. 549. Fig. 550. yellowish, brick-, and flesh-red. Sol. in h. acid, leaving silica. C.c. : silica 47 8, alumina 20 8, lime 107, water 21 "3. Lyndale (figs. 547, 548, 549), Talisker (figs. 176, 550, sometimes flesh Fig. 551. Fig. 552. colour), and Storr, Skye (figs. 547, 548); Port Glasgow and Kil- malcolm (pink and brown) ; Giant s Causeway and Magee Island (red), Faroes, Iceland, Aussig, Andreasberg (fig. 551). Haydenite in twinned rhombohedra, with p : p 95 to 97 and p : d 170 reentering (fig. 552), from Fassa and Maryland, is similar. Phacolite is chabasite in twins of |P2, o>P2, R, -JR at the Giant s Causeway (fig. 154). At Richmond in Victoria g 55 -rc- |R W |P2 (t), OP (c) ; polar edge, |P2 145 . In this, half of the lime is replaced by soda. 609. GMELINITE (Soda-Chabasite), AlSi 3 + NaSi + 6H .
Hexagonal. R 112 26 ; P 79 54 . Combination P, OP, ooP