The Chemistry, Properties and Tests of Precious Stones

by John Mastin

INDEX

Adamantine lustre, [28]
glimmering, [29]
glinting, or glistening, [29]
lustreless, [29]
shining, [29]
splendent, [29]
Agate, [11]
Almandine, [101]
Amethyst, [11]
oriental, [85]
sapphire, [85]
Amorphous stones and their characteristics, [23]
Analysis, [5]
Aplome, [101]
Asters, or asteriated stones, [82], [87]-91
Azure-stone, [103]
Beryl, [10], [94]
colours of, in dichroscope, [34]
Beryllium, [10]
Bezils, [66]
Black stones, list of, [79]
Blue sapphire, composition of the, [10]
stones, list of, [77]
Bone-turquoise, [106]
Break, as opposed to cleavage, [19]
Brilliant-cut stones, [66]
Brown stones, list of, [76]
Building up of crystals, [13]
Burnt, or pinked topaz, [92]
Cabochon-cut stones, [64]
(the double), [65]
(the hollow), [65]
Carbonate series, [11]
Carbuncle, [102], [103]
Cat of Egypt, [89]
Cat's eye stones, [82], [87]-91
list of (see "Chatoyant Stones"), [78]
Ceylonese cat's eye (see "Cat's eye")
Change of colour (not to be confused with "Play of colour" and "Opalescence," which see; see also "Fire"), [36]
Characteristics of precious stones, [1], [3]
Chatoyant stones, list of, [78]
Chemical illustration of formation of precious stones, [8]
Chloride of palladium in dichroscope, [34]
Chrysoberyl, [88]
Chrysolite, [11]
ordinary, or "noble", [85]
oriental, [85]
Cinnamon stone, [102]
Claims of precious stones, [4]
Cleavage affecting tests, [43]
and "cleavage" as opposed to "break", [19], [22]
Colour, [26], [28], [30], [32]
Colourless stones, list of, [75]
Colours and characteristics of the various opals, [35], [36]
of precious stones, list of, [75]-79
Common garnet, [101]
opal, [35]
Composite crystals, [13]
Composition of paste, or strass, for imitation stones, [71]
Composition of precious stones, [7]
Converted stones, [72]
Corundum, [82]
Crown portion of stones, [65], [66]
Crystalline structure, physical properties, of [13]
Crystallography, [14]
Crystals, axes of symmetry, [15]
groups of, [15], [16]
planes of symmetry, [15]
systems of, [16]
(1) Cubic—isometric, monometric, regular, [16]
(2) Hexagonal—rhombohedral, [16]
(3) Tetragonal—quadratic, square prismatic, dimetric, pyramidal, [16]
(4) Rhombic—orthorhombic, prismatic, trimetric, [16]
(5) Monoclinic—clinorhombic, monosymmetric, oblique, [16], [17]
(6) Triclinic—anorthic, asymmetric, [16], [17]
treatment of, [14]
Culasse portion of stones, [66]
Cullinan diamond (see also "Stars of Africa"), [22], [64], [68], [80]
Cutting of precious stones, [3], [4], [62]
Cymophane, [90]
Definition of a precious stone, [1]
Diamond, characteristics of the, [80]
composition of the, [10]
(sapphire), [86]
unique, [10]
(zircon), [99]
Diaphaneity, [26], [28]
Diaphanous stones, [28]
Dichroscope, [33]
how to make a, [33]
how to use a, [34]
Dimorphism in precious stones, [25]
Double cabochon-cut stones, [65]
refraction (see "Refraction")
Doublets, [72]
Electric and magnetic influences, [57]
experiments with precious stones and pithball and electroscope, [57]
experiments with tourmaline, [58], [59]
Emerald, [10], [11], [95], [96]
oriental, [85]
En cabochon-cut stones, [64]
Experiments to show electric polarity, [58], [59]
Facets in stones, description of the, [67], [68]
Feminine stones, [85]
Fire in stones (see also "Change of Colour," "Opalescence," and "Play of Colour"), [36], [37]
Fire opal, [35]
Flame-coloured stones, list of, [76]
Flaws, [63]
Formation of precious stones, [5], [8]
chemical illustration of, [8], [9]
Garnet, [11], [100]
Garnets
(A) iron-alumina (called also almandine and precious or oriental garnet), [101]
sub-variety, common garnet, [101]
(B) lime-iron, [101]
sub-variety aplome, [101]
melanite, [101]
pyreneite, [101]
topazolite, [101]
(C) lime-chrome, [101], [102]
sub-variety uwarowite, [101], [102]
(D) lime-alumina, [102]
sub-variety cinnamon stone, [102]
romanzovite, [102]
succinite, [102]
(E) magnesia-alumina, [102], [103]
sub-variety carbuncle, or anthrax, [102], [103]
noble, [103]
pyrope, [102]
(F) manganese-alumina, [103]
sub-variety spessartine, or spessartite, [103]
Girdle portion of a stone, [66]
Glimmering, in lustre, definition of, [29]
Glinting, or glistening in lustre, definition of, [29]
Goutte de suif-cut stones, [65]
Great Mogul diamond, [64]
Green stones, list of, [78]
Groups of crystals (see "Crystals")
Hardness, physical properties of, [39]
table of, [39], [40], [41]
Heat indexes, [54]
physical properties of, [52]
Hollow-cabochon, [65]
Hyacinth, ordinary (a form of zircon), [85], [98]
oriental, [85]
Hyalite (opal), [35]
Hydrophane (opal), [35]
Imitations and tests of precious stones, [70]
Indigo sapphires, [86]
Ink sapphires, [85]
Iridescence, and cause of, [37], [38]
Iron-alumina garnets, [101]
Jacinth, oriental, [85]
Jarcon, or jargoon, [98]
Koh-i-nûr, [64]
Lapis-lazuli, [103]
Light, physical properties of, [26]
Lime-alumina garnets, [102]
cinnamon stone, [102]
romanzovite, [102]
succinite, [102]
Lime-chrome garnets, [101], [102]
uwarowite, [101], [102]
Lime-iron garnets, [101]
aplome, [101]
pyreneite, [101]
topazolite, [101]
List of stones according to colour, [75]-79
hardness, [39]-41
specific gravity, [48]-50
Lustre, [26], [28]
Lustreless, definition of, [29]
Lynx-eye stones, [87]
Magnesia-alumina garnets, [102], [103]
carbuncle, or anthrax, [102]
noble, [103]
pyrope, [102]
Magnetic and electric influences, [57]-61
Malachite, [11]
Manganese-alumina garnets, [103]
spessartine, or spessartite, [103]
Masculine stones, [85]
Melanite, [101]
Menilite (opal), [36]
Metallic-lustre stones, [28], [29]
Mohs's table of hardness, [39]-41
Noble garnet, [103]
or precious opal, [35]
Non-diaphanous stones, [28]
Odontolite, [106]
Olivine corundum (see "Chrysolite"), [85]
Opal, [11]
varieties of, [35], [36]
Opalescence (not to be confused with "Change of Colour" and "Play of Colour," which see; see also "Fire"), [36], [37]
Oriental amethyst, [85]
cat's eye (see "Cat's eye")
emerald, [85]
garnet, [101]
topaz, [85]
Origin of precious stones, [7]
Paste, or strass, for imitation stones, composition of, [71]
Pavilion portion of cut stones, [66]
Pearly-lustre stones, [28], [29]
Peridot (see "Noble Chrysolite"), [85]
Pink-coloured stones, list of (see also Red), [77]
Pinked topaz, [92]
Phosphorescence, [26], [30]
Physical properties:—
A.—Crystalline structure, [13]
B.—Cleavage, [19]
C.—Light, [26]
D.—Colour, [32]
E.—Hardness, [39]
F.—Specific gravity, [45]
G.—Heat, [52]
H.—Magnetic and electric influences, [57]
Play of colour (not to be confused with "Change of Colour" and "Opalescence," which see; see also "Fire"), [36], [37]
Pleochroism, [33]
Polarisation, electric, [58], [59]
of light, [26], [27]
Polariscope, [27], [28]
Polishing precious stones, [3], [4]
Polymorphism in precious stones, [25]
Precious, or noble opal, [35]
Pseudomorphism in precious stones, [23], [24]
Pyreneite, [101]
Pyro-electricity, development and behaviour of, [58]-60
Pyrope, [102]
Qualities of precious stones, [1], [3]
Red and rose-coloured stones, list of (see also Pink), [76], [77]
Reflection of light, [26], [28]
Refraction of heat, [52]-55
light, [26], [27]
Reproduction of crystalline form, [20], [21]
Resinous lustre stones, [28], [29]
Rock-crystal, [11]
Romanzovite, [102]
Rose-coloured stones (see Red, above), [76], [77]
Rose, or rosette-cut stones, [65]
Rothschild's testing solution, [73]
Ruby, characteristics of, [83]
composition of, [10]
Sapphire, amethyst, [85]
and its varieties, [84], [85]
cleared, [86]
diamonds, [87]
indigo, [86]
ink, [85]
the blue, composition of, [10], [85]
water, [86]
Semi-diaphanous stones, [28]
Shining, in lustre, definition of, [29]
Silica group, composition of the, [11]
Silicates, [100]
Silky-lustre stones, [28], [29]
Single-refraction (see "Refraction")
South African diamond (see "Cullinan Diamond")
Specific gravity, [45]
Splendent, in lustre, definition of, [29]
Splitting of the Cullinan diamond, [22]
Star-portion of stones, [65]
Stars of Africa (see also "Cullinan Diamond"), [22], [64], [68]
Starting or splitting of stones on cleavage planes, [23]
Step-cut stones, [66]
Stones arranged according to colour, [75]-79
hardness, [39]-41
specific gravity, [48]-50
Strass for imitation stones, composition of, [71]
Sub-metallic in lustre, definition of, [29]
Sub-translucent stones, [28]
Sub-transparent stones, [28]
Succinite, [102]
Synthesis, [5]
Systems of crystals (see "Crystals")
Table-cut stones, [65]
Tallow drops, [65]
Teeth of stone, [65]
Testing by crystalline structure, [17]
hardness, [40], [43]
with needles, [41]
gems by dichroscope, [33], [34]
solution (Rothschild's), [73]
Tests of precious stones (general), [70]
Topaz, [11], [91]
colours of, in dichroscope, [34]
oriental, [85]
Topazolite, [101]
Tourmaline, [96], [97]
electric experiments with, [58], [59]
Translucent stones, [28]
Transmission of heat, [52]-56
light, [26]
Transparent stones, [28]
Trap-cut stones, [66]
Tri-morphism in precious stones, [25]
Triplets, [72]
Turquoise, [104]
(bone), [106]
composition of the, [11]
odontolite, [106]
Uwarowite, [101], [102]
Violet stones, list of, [78]
Vitreous-lustre stones, [28], [29]
Water-sapphires, [86]
White (paste) stones, [71]
stones, list of, [75]
Yellow stones, list of, [76]
topaz, [92]
Zircon, [10], [98]
diamonds, [99]
Zirconium, [10]

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