154^ 
NON-METALLIC MINERALS. 
410. Fluor Spar, in green 
octohedral crystals built up of 
minute cubes. 
Devonshire. f 
411. Fluor Spar, in large blue | 
cubes, having the solid angles re- i 
2 :laced by planes of the hexakis- i 
octohedron, with Iron Pyrites. ! 
Menhenioi Mines, Cornwall. ' 
412. Fluor Spar, crystallized i 
in combination of cube and 
hexakis-octohedron, exhibiting 
internal parallel j)lanes of deposi¬ 
tion ; with Galena. 
Menheniot Mines, Cornwall. 
413 & 414. F'luor Spar, crys¬ 
tallized in combination of tetrakis- 
hexahedron and rhombic dodeca¬ 
hedron. 
St. Agnes, Cornwall. 
415. Fluor Spar, colourless. 
From the Lead lode, at the 130 
fathoms level, Holmhush Mine, 
near Callington, Cornwall. 
416. Fluor Spar, massive un- 
cleavable variety, highly phos¬ 
phorescent on exposure to heat. 
East Pool Mine, near Fedruth, 
Cornwall. 
Presented by the late John Garby. 
417. Fluor Spar, octohedral 
crystals converted into hornstone. 
Huel Mary Ann, Cornwall. 
418. Tablet supporting speci¬ 
mens of cleaved Fluor Spar. 
1 to 3. Regular Octohedrons. 
4. Regular Tetrahedron. 
5. Acute Rhombohedron. 
419. Fluor Spar, green, crys¬ 
tallized in combination of cube and 
octohedron. 
Stolherg, Hartz. 
420. Fluor Spar, green, in 
cubo-octohedral crystals, with 
CopjDer Pyrites. 
Ttottleberode, Hartz. 
421. Prosopite, a steatitic 
pseudomorph after a paramorjDhic 
variety of ^^urple Fluor Spar ; with 
FIgematite, and Fluor. 
From the Tin Mines of Altenherg 
Saxony. 
Presented by H. Baueiman, F.G.S. 
Case H. 
Two cases are devoted to the carbonate of Lime, it being impossible; 
within a smaller com^^ass to give a fair rei^resentation of the manifold 
appearances of that compound. Besides the many hundred different 
forms of crystal in which Calcite, or the hexagonal carbonate, is found, 
there is a long series of figures assumed by Aragonite, the rhombic 
carbonate, and both S 2 )ecies ap^iear in a great variety of conditions, 
crystalline, stalactitic, or conijoact, and more or less tinted and variegated 
by colouring substances. Hence the interminable wealth of pattern and 
colour which nature j)resents to us in the marbles. A single country 
may thus require a large suite of specimens for its full illustratiou, more 
j^articularly if the object of the collection be purely artistic. A large 
number of examples of our Derbyshire and Devonshire marbles are 
exhibited in the lower hall, and a far more extensive series would have 
to be shown were it the object of the Museum to illustrate the marbles 
of either the Pyrenees, Italy, or Strain. 
Calcite. 
422. Calcite, or Calcareous 
Sjiar {Carbonate of Lime). 
Strontian, Argyleshire. 
423. Calcite, with annular Iron 
Pyrites enclosing radiated Barytes. 
Strontian. 
424. Calcite, crystallized in 
the hexagonal prism penetrated by 
a rhombohedron, the solid angle 
of which 2 )artly ^Drotrudes from the 
terminal j)lane of the iirism. 
St7'o?itian. 
