TABLE 276.— COMPRESSIBILITY OF CRYSTALS** 287 



Part 1. — — AV/V = aP — bP 2 where P is in bars (10 9 dyne/cm 2 ) and V is the volume 

 at 1 atm and 30°C (or room temp.) 



Pressure range, 1-12,000 bars 



Crystal and formulae System 



Andradite : 



3CaO-Fe 2 3 -3Si0 2 Cubic 



Apatite: 3Ca 3 P2CvCaF 2 .. Hexagonal 



Argentite : Ag 2 S Cubic 



Barite : BaS0 4 Orthorhombic 



Beryl: 3BeO-Al,CV6SiO.. Hexagonal 



Calcite : CaC0 3 Trigonal 



Cobaltite : CoAs-S Cubic 



Fluorite : CaF 2 Hexagonal 



Galena : PbS Cubic 



Garnet (pyrope) : 



3MgO-Al,CV3SiOi .... Cubic 



Halite (Rock Salt): NaCl. Cubic 

 Hanksite : 



KCl-2Na 2 CGv9Na 2 SC>4 . Hexagonal 



Jeffersonite Monoclinic 



Lithium fluoride : LiF Cubic 



Lithium iodide : Lil Cubic 



Magnetite : Fe 3 04 Cubic 



Orthoclase : KAl-SiaOs ... Monoclinic 



Periclase : MgO Cubic 



Potassium bromide : KBr . Cubic 



Potassium fluoride : KF . . . Cubic 



Potassium iodide : KI .... Cubic 



Pyrite : FeS2 Cubic 



Quartz : a SiOa Trigonal 



Rochelle salt (see end of part 1) 

 Sapphire (synthetic) : AI2O3 



Sphalerite : ZnS Cubic 



Spodumene : Li Al ■ Si a Oe . . . Monoclinic 



Sylvite : KC1 Cubic 



Tourmaline (black) Trigonal 



Topaz 



Zircon: ZrGvSi0 2 



Pressures 

 kg/cm2 



Rochelle salt: GH,OcKNa : 



2000 



4000 



6000 



8000 



10,000 



12,000 



8.6 

 - a v/v 



.01080 

 .02016 

 .02885 

 .03716 

 .04501 

 .05237 



For reference, see footnote 45, p. 136. 



{continued) 



SMITHSONIAN PHYSICAL TABLES 



