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"Ruby, emerald, blue sapphire, cat's eye, yellow sapphire, diamond, pearl, hessonite, coral, bloodstone, quartz, jade, and red garnet are the foremost species of gems, and they should be selected only under the expert guidance of a learned gemologist." ---Sri Garuda-puranam (Circa 3,000 BC)

The basic gemological characteristics of the principal gemstones used in astral gem therapy are listed below. These factors are used by gemologists throughout the world today to scientifically identify and grade the quality of precious gems. Combined with the astrological attributes of gems discussed in the foregoing chapters, this gemological information gives a complete picture of the nature of each gemstone.

Gems are listed according to the planet with which each type of stone is astrologically associated, beginning with the Sun. Present sources and other information will be limited to those sources and characteristics which pertain to "gem" (auspicious) quality only.

Please CLICK here to go to : Gemstones of the
Sun - Moon - Jupiter - Rahu - Mercury - Venus - Ketu - Saturn - Mars

Gemstones of the Sun

1) RUBY

Present Sources: Burma, Thailand, Sri Lanka, Cambodia, Laos & Vietnam

Gemological Characteristics
  • SPECIES: corundum
  • TRANSPARENCY: transparent
  • COLOR: red, orangish-red, violetish-red, purplish-red, pinkish-red & blackish-red.
  • REFRACTIVE INDEX: 1.763-1.770
  • BIREFRINGENCE: 0.008
  • PLEOCHROISM: strong dichroism
  • CRYSTAL SYSTEM: hexagonal
  • OPTIC CHARACTER: doubly refractive
  • SPECIFIC GRAVITY: 4.00 MOHS
    HARDNESS: 9
  • DISPERSION: 0.018
  • FLUORESCENCE: long wave-weak to strong red
  • IDENTIFYING VISUAL CHARACTERISTICS: fingerprint inclusions, hexagonal growth lines, silk (rutile), and straight color banding.

2) RED SPINEL

Present Sources: Sri Lanka, Burma and Thailand

Gemological Characteristics
  • SPECIES: spinel
  • TRANSPARENCY: transparent
  • COLOR: red, pink-red, pink, purple-red, violet- red, orange-brownish red
  • REFRACTIVE INDEX: 1.718
  • CRYSTAL SYSTEM: cubic
  • OPTIC CHARACTER: singly refractive
  • SPECIFIC GRAVITY: 3.60 MOHS
  • HARDNESS: 8
  • DISPERSION: .020
  • FLUORESCENCE: long wave-weak to strong red-orange, short wave-inert to weak red.
  • IDENTIFYING VISUAL CHARACTERISTICS: natural inclusions, e.g., needles, fingerprint inclusions of spinel octahedra, etc.

3) RED GARNET

Present Sources:
Almandite: Burma, India, Sri Lank, Brazil, Western U.S.A. and many other areas around the world.
Rhodolite: Sri Lanka, U.S.A., and E. Africa.
Pyrope: U.S.A., Czechoslovakia, Australia, South Africa, Brazil, Sri Lanka and Madagascar.

Gemological Characteristics
  • SPECIES (1): almandite
  • TRANSPARENCY: transparent
  • COLOR: violetish-red to brownigh-red
  • REFRACTIVE INDEX: 1.790
  • CRYSTAL SYSTEM: cubic
  • OPTIC CHARACTER: singly refractive
  • SPECIFIC GRAVITY: 4.05 MOHS
  • HARDNESS: 71/2
  • DISPERSION: .024
  • IDENTIFYING VISUAL CHARACTERISTICS: needlelike inclusions frequently intersecting at 70o and 110o in same plane, coarse stubby silk, and doubly refractive colorless grain-like inclusions.

  • SPECIES(2): rhodolite
  • TRANSPARENCY: transparent
  • COLOR: red to violet
  • REFRACTIVE INDEX: 1.76
  • CRYSTAL SYSTEM: cubic
  • OPTIC CHARACTER: singly refractive
  • SPECIFIC GRAVITY: 3.84 MOHS
  • HARDNESS: 7-7 1/2
  • DISPERSION: .026
  • INDENTIFYING VISUAL CHARACTERISTICS: same as almandite (typical garnet inclusions); purplish-red color and variable refractive index of 1.75 - 1.77 possible.

  • SPECIES(3): pyrope
  • TRANSPARENCY: transparent
  • COLOR: brownish red
  • REFRACTIVE INDEX: 1.746
  • CRYSTAL SYSTEM: cubic
  • OPTIC CHARACTER: singly refractive
  • SPECIFIC GRAVITY: 3.78 MOHS
  • HARDNESS: 7-7 1/2
  • DISPERSION: .027
  • IDENTIFYING VISUAL CHARACTERISTICS: typical garnet inclusions, same as almandite.

4) RUBELLITE

Present Sources Sri, Lanka, Burma, South West Africa, Ural Mountains (Russia), Brazil, Madagascar, Maine and California (USA).

Gemological Characteristics
  • SPECIES: tourmaline
  • TRANSPARENCY: transparent
  • COLOR: pink to red
  • REFRACTIVE INDEX: 1.62-1.64
  • BIREFRINGENCE: .020
  • PLEOCHROISM: strong dichroism
  • CRYSTAL SYSTEM: hexagonal
  • OPTIC CHARACTER: doubly refractive
  • SPECIFIC GRAVITY: 3.06 MOHS
  • HARDNESS: 7-7 1/2
  • DISPERSION: .017
  • FLUORESCENCE: not significant
  • IDENTIFYING VISUAL CHARACTERISTICS: color zoning, natural inclusions, e.g., threadlike gas inclusions, liquid and and moderate doubling of back facets.

Gemstones of the Moon

1) PEARL

Present Sources Natural Oyster Pearl -- Persian Gulf (Bahrain), Sri Lanka, Venezuela, Bengal, Bombay, Australia and the South Seas.

Gemological Characteristics
  • SPECIES: natural pearl
  • TRANSPARENCY: translucent to opaque
  • COLOR: white, pink rose, cream, yellowish, greenish, blue, gray and black
  • REFRACTIVE INDEX: 1.530-1.686
  • CRYSTAL SYSTEM: aggregate
  • SPECIFIC GRAVITY: 2.70 MOHS
  • HARDNESS: 2 1/2 - 4 1/2
  • FLUORESCENCE: long wave-inert to strong, short wave-inert to moderate.
  • IDENTIFYING VISUAL CHARACTERISTICS: orient, gritty texture when rubbed on teeth, best test to separate natural from cultured is X-radiograph.

2) MOONSTONE

Present Sources Sri Lanka, Burma, Central and Southern India.

Gemological Characteristics
  • SPECIES: orthoclase feldspar
  • TRANSPARENCY: transparent to translucent
  • COLOR: colorless and white with white/bluish adularescence
  • REFRACTIVE INDEX: 1.518-1.526
  • BIREFRINGENCE: .008
  • PLEOCHROISM: weak dichorism
  • CRYSTAL SYSTEM: monoclinic
  • OPTIC CHARACTER: doubly refractive
  • SPECIFIC GRAVITY: 2.56 MOHS
  • HARDNESS: 6 - 6 1/2
  • DISPERSION: .012
  • FLUORESCENCE: not significant
  • IDENTIFYING VISUAL CHARACTERISTICS: adularescence (floating white/bluish light), near perfect cleavage, splintery/ uneven fracture, centipede inclusions.

Gemstones of Jupiter

1) YELLOW SAPPHIRE

Present Sources Sri Lanka, Thailand, Burma and Cambodia.

Gemological Characteristics
  • SPECIES: corundum
  • TRANSPARENCY: transparent
  • COLOR: light-yellow,yellow,golden-yellow, brownish yellow, golden,orangishyellow, golden orange, and pinkish orange (padparadscha )
  • REFRACTIVE INDEX: 1.762-1.770
  • BIREFRINGENCE: 0.008
  • PLEOCHROISM: strong dichroism
  • CRYSTAL SYSTEM: hexagonal
  • OPTIC CHARACTER: doubly refractive
  • SPECIFIC GRAVITY: 4.00 MOHS
  • HARDNESS: 9
  • DISPERSION: 0.018
  • FLUORESCENCE: colorless sapphire--inert to strong reddish (long- wave), inert to moderate orange (short wave).
  • IDENTIFYING VISUAL CHARACTERISTICS: fingerprint inclusions, hexagonal growth lines, silk (rutile), and straight color banding

2) YELLOW TOPAZ

Present Sources Brazil, Sri Lanka, Africa, Mexico and U.S.A.

Gemological Characteristics
  • SPECIES : topaz
  • TRANSPARENCY : transparent
  • COLOR : yellow, golden, sherry, pinkish-yellow, yellow-brown, brownish-orange
  • REFRACTIVE INDEX : 1.619 - 1.627
  • BIREFRINGENCE : .008
  • PLEOCHROISM : weak to strong dichroism and trichroism
  • CRYSTAL SYSTEM : orthorhombic
  • OPTIC CHARACTER : doubly refractive
  • SPECIFIC GRAVITY : 3.52 MOHS
  • HARDNESS : .014
  • FLUORESCENCE : long wave - inert to weak yellow
  • IDENTIFYING VISUAL CHARACTERISTICS : liquid/gas and other natural inclusions, basel cleavage, possible 3-phase inclusions, and "rhombic" (four sided) etch markings.

3) CITRINE

Present Sources Brazil, Madagascar, Uruguay, and many other minor sources throughout the world.

Gemological Characteristics
  • SPECIES : quartz
  • TRANSPARENCY : transparent
  • COLOR : yellow, golden, orangish yellow, and brownish yellow
  • REFRACTIVE INDEX : 1.544 - 1.553
  • BIREFRINGENCE : .009
  • PLEOCHROISM : weak to strong dichroism
  • CRYSTAL SYSTEM : hexagonal
  • OPTIC CHARACTER : doubly refractive
  • SPECIFIC GRAVITY : 2.66 MOHS
  • HARDNESS : 7
  • DISPERSION : .013
  • FLUORESCENCE : not significant
  • IDENTIFYING VISUAL CHARACTERISTICS : vitreous conchoidal fracture, liquid inclusions, 2-phase inclusions, negative crystals, color zoning or banding, and uneven coloration

4) HELIODOR

Present Sources Brazil, Russia (Sverdlovsk), Madagascar, U.S.A. (So.California), South Africa, and a few other areas around the world.

Gemological Characteristics
  • SPECIES : beryl
  • TRANSPARENCY : transparent
  • COLOR : light to golden yellow
  • REFRACTIVE INDEX : 1.577 - 1.583
  • BIREFRINGENCE : .005 to .009
  • PLEOCHROISM : weak greenish yellow and yellow
  • CRYSTAL SYSTEM : hexagonal
  • OPTIC CHARACTER : doubly refractive
  • SPECIFIC GRAVITY : 2.67 to 2.84 MOHS
  • HARDNESS : 7 1/2
  • DISPERSION : .014
  • FLUORESCENCE : none
  • IDENTIFYING VISUAL CHARACTERISTICS : typical 3 phase and 2 phase inclusions, inclusions of calcite, pyrite, mica and/or tremolite needles, etc.

Gemstones of Rahu

1) HESSONITE

Present Sources Sri Lanka, Africa, India and Burma.

Gemological Characteristics
  • SPECIES : grossularite
  • TRANSPARENCY : transparent
  • COLOR : golden orange, brownish orange and reddish orange
  • REFRACTIVE INDEX : 1.74 - 1.75
  • CRYSTAL SYSTEM : cubic
  • OPTIC CHARACTER : singly refractive
  • SPECIFIC GRAVITY : 3.61 MOHS
  • HARDNESS : 7
  • DISPERSION : 0.028
  • FLUORESCENCE : inert
  • IDENTIFYING VISUAL CHARACTERISTICS : roiled (heat-wave) internal appearance, garnet inclusions, anomalous double refraction and strain colors may be visible in polariscope.

2) ORANGE ZIRCON

Present Sources Burma, Sri Lanka, Thailand and Viet Nam

Gemological Characteristics
  • SPECIES : zircon
  • TRANSPARENCY : transparent
  • COLOR : yellow-orange, orange, orange-red, reddish-brown & brown
  • REFRACTIVE INDEX : 1.875 (medium), 1.925 - 1.984 (high)
  • BIREFRINGENCE : .006 - .050 (medium), .059 (high)
  • PLEOCHROISM : weak to strong dichroism
  • CRYSTAL SYSTEM : tetragonal
  • OPTIC CHARACTER : doubly refractive
  • SPECIFIC GRAVITY : 4.32 (medium), 4.70 (high) MOHS
  • HARDNESS : 7 1/2
  • DISPERSION : .038
  • FLUORESCENCE : short wave-inert to strong orange and/or inert to strong yellow, long wave-inert to moderate yellow
  • IDENTIFYING VISUAL CHARACTERISTICS : strong doubling of back facet junctions, abraded facet edges, sub-admantine luster, natural inclusions.

3) SPESSARTITE

Present Sources Sri Lanka, Burma, Madagascar, Brazil, Australia, and U.S.A.

Gemological Characteristics
  • SPECIES: spessartite
  • TRANSPARENCY: transparent
  • COLOR: golden orange to orangish-red
  • REFRACTIVE INDEX: 1.810
  • CRYSTALL SYSTEM: cubic
  • OPTIC CHARACTER: singly refractive
  • SPECIFIC GRAVITY: 4.15 MOHS
  • HARDNESS: 7-7 1/2
  • DISPERSION: .027
  • IDENTIFYING VISUAL CHARACTERISTICS: needlelike inclusions frequently intersecting at 70o and 110o in same plane, coarse stubby silk, and doubly refractive colorless grain-like inclusions.

Gemstones of Mercury

1) EMERALD

Present Sources South America (primarily Columbia and Brazil), Africa (Sandewana, Kenya, Tanzania, Zambia, Mozambique), India, Pakistan, Russia (Ural Mountains), and Egypt.

Gemological Characteristics
  • SPECIES : beryl
  • TRANSPARENCY : transparent
  • COLOR : green, yellowish-green and bluish green
  • REFRACTIVE INDEX : 1.577 - 1.583
  • BIREFRINGENCE : 0.005 - 0.009
  • PLEOCHROISM : weak to strong dichroism
  • CRYSTAL SYSTEM : hexagonal
  • OPTIC CHARACTER : doubly refractive
  • SPECIFIC GRAVITY : 2.72 MOHS
  • HARDNESS : 7 1/2 - 8
  • DISPERSION : 0.014
  • FLUORESCENCE : inert to weak green (long and shortwave)
  • IDENTIFYING VISUAL CHARACTERISTICS : typical 3 phase and 2 phase inclusions, inclusions of calcite, pyrite, mica and/or tremolite needles, etc.

2. GREEN JADE

Present Sources Jadeite - Burma; Nephrite - China, New Zealand and U.S.A.

Gemological Characteristics
  • SPECIES (1) : jadeite
  • TRANSPARENCY : transluent
  • COLOR : intense green to mottled green
  • REFRACTIVE INDEX : 1.660 - 1.668 (1.66)
  • CRYSTAL SYSTEM : monoclinic (aggregate)
  • SPECIFIC GRAVITY : 3.34 MOHS
  • HARDNESS : 6 1/2 - 7
  • IDENTIFYING VISUAL CHARACTERISTICS : greasy to waxy luster, spectroscopic reading of 4370 at the edge of the violet is conclusive identity of translucent, light-colored jadeite.
  • SPECIES (2) : nephrite
  • TRANSPARENCY : translucent
  • COLOR : dark green
  • REFRACTIVE INDEX : 1.61 - 1.63 (1.61)
  • CRYSTAL SYSTEM : monoclinic (aggregate)
  • SPECIFIC GRAVITY : 2.95 MOHS
  • HARDNESS : 6 - 6 1/2
  • IDENTIFYING VISUAL CHARACTERISTICS : rough fracture with dull luster. Black inclusions may be visible.

3) PERIDOT

Present Sources Burma, Zebirget Island (Red Sea), Arizona (USA).

Gemological Characteristics
  • SPECIES : peridot
  • COLOR : green, yellow-green, brownish-green
  • REFRACTIVE INDEX : 1.654 - 1.690
  • BIREFRINGENCE : .036
  • PLEOCHROISM : weak dichroism
  • CRYSTAL SYSTEM : orthorhombic
  • OPTIC CHARACTER : doubly refractive
  • SPECIFIC GRAVITY : 3.34 MOHS
  • HARDNESS : 6 1/2 - 7
  • DISPERSION : .020
  • FLUORESCENCE : not significant
  • IDENTIFYING VISUAL CHARACTERISTICS : vitreous conchoidal fracture, strong doubling of back facets, natural inclusions, e.g., lily pad, black chromite crystals and iron oxide inclusions.

4) GREEN TOURMALINE

Present Sources Sri Lanka, Burma, South West Africa, Ural Mountains (Russia), Brazil, Madagascar, Maine and California (USA).

Gemological Characteristics
  • SPECIES : tourmaline
  • TRANSPARENCY : transparent
  • COLOR : chrome-green, yellow-green, blue-green & brownish-green
  • REFRACTIVE INDEX : 1.62 - 1.64
  • BIREFRINGENCE : .020
  • PLEOCHROISM : strong dichroism
  • CRYSTAL SYSTEM : hexagonal
  • OPTIC CHARACTER : doubly refractive
  • SPECIFIC GRAVITY : 3.06 MOHS
  • HARDNESS : 7 - 7 1/2
  • DISPERSION : .017
  • FLUORESCENCE : not significant
  • IDENTIFYING VISUAL CHARACTERISTICS : color zoning, natural inclusions, e.g., threadlike liquid and gas inclusions, and moderate doubling of back facets.

5) TSAVORITE

Present Sources Kenya and Tanzania in Africa

Gemological Characteristics
  • SPECIES : grossularite
  • TRANSPARENCY : transparent COLOR : chrome green
  • REFRACTIVE INDEX : 1.73 - 1.75
  • CRYSTAL SYSTEM : cubic
  • OPTIC CHARACTER : singly refractive
  • SPECIFIC GRAVITY : 3.61 (3.30 - 4.30) MOHS
  • HARDNESS : 7 - 7 1/4
  • DISPERSION : .028
  • FLUORESCENCE : long and short wave-inert to red
  • IDENTIFYING VISUAL CHARACTERISTICS : stubby, rounded included crystals of low relief, occasional needles, fractures, and bubbly-veils.

6) GREEN DIOPSIDE

Present Sources Brazil, Sri Lanka, Italy and USA

Gemological Characteristics
  • SPECIES : diopside
  • TRANSPARENCY : transparent COLOR : chrome green (recommended color)
  • REFRACTIVE INDEX : 1.675 - 1.701
  • BIREFRINGENCE : .026
  • PLEOCHROISM : weak dichroism and trichroism
  • CRYSTAL SYSTEM : monoclinic
  • OPTIC CHARACTER : doubly refractive
  • SPECIFIC GRAVITY : 3.29+/- .03 MOHS
  • HARDNESS : 5 - 6 DISPERSION : n/a
  • IDENTIFYING VISUAL CHARACTERISTICS : confused with peridot but with lower birefringence and higher refractive index.

Gemstones of Venus

1) DIAMOND

Present Sources Africa (Botswana, Tanzania, Sierra Leone, Angola, Republic Liberia and Ivory Coast), Brazil, Venezuela, Guyana, Indonesia, India, Russia and Australia.

Gemological Characteristics
  • SPECIES : diamond
  • TRANSPARENCY : transparent
  • COLOR : colorless to tints of yellow, brown, blue, pink, chartreuse and black
  • REFRACTIVE INDEX : 2.417
  • CRYSTAL SYSTEM : cubic
  • OPTIC CHARACTER : singly refractive
  • SPECIFIC GRAVITY : 3.52 MOHS
  • HARDNESS : 10
  • DISPERSION : 0.044
  • FLUORESCENCE : inert to very strong bluish-white (long and short wave)
  • IDENTIFYING VISUAL CHARACTERISTICS : adamantine luster, naturals, waxy to rough girdle surface, sharpness offacet edges, reflectivity meter of diamond probe helps separate diamonds from substitutes.

2) ROCK CRYSTAL

Present Sources Nepal, India, Pakistan, Brazil and practically every country in the world.

Gemological Characteristics
  • SPECIES : quartz
  • TRANSPARENCY : transparent
  • COLOR : white (colorless)
  • REFRACTIVE INDEX : 1.544 - 1.553
  • BIREFRINGENCE : .009
  • CRYSTAL SYSTEM : hexagonal
  • OPTIC CHARACTER : doubly refractive
  • SPECIFIC GRAVITY : 2.66 MOHS
  • HARDNESS : 7
  • DISPERSION : .013
  • FLUORESCENCE : nil
  • IDENTIFYING VISUAL CHARACTERISTICS : conchoidal fracture with vitreous luster on fracture surface, negative liquid and crystal inclusions.

3) WHITE ZIRCON

Present Sources Sri Lanka, Burma, Thailand and Vietnam

Gemological Characteristics
  • SPECIES : zircon
  • TRANSPARENCY : transparent
  • COLOR : colorless
  • REFRACTIVE INDEX : 1.875 - 1.905 (medium), 1.925 - 1.984 (high)
  • PLEOCHROISM : weak to strong dichroism
  • CRYSTAL SYSTEM : tetragonal
  • OPTIC CHARACTER : doubly refractive
  • SPECIFIC GRAVITY : 4.32 (medium), 4.70 (high) MOHS
  • HARDNESS : 7 1/2
  • DISPERSION : .038
  • FLUORESCENCE : not significant
  • IDENTIFYING VISUAL CHARACTERISTICS : natural angular inclusions, abraded facet junctions, strong doubling of back facets.

4) GOSHENITE

Present Sources Sri Lanka, Brazil, Madagascar, Russia, California and Maine.

Gemological Characteristics
  • SPECIES : beryl
  • TRANSPARENCY : transparent
  • COLOR : white (colorless)
  • REFRACTIVE INDEX : 1.577 - 1.583 (generally low)
  • BIREFRINGENCE : .005 - .009 (generally low)
  • PLEOCHROISM : weak to dichroism
  • CRYSTAL SYSTEM : hexagonal
  • OPTIC CHARACTER : doubly refractive
  • SPECIFIC GRAVITY : 2.72 MOHS
  • HARDNESS : 7 1/2
  • DISPERSION : .014
  • FLUORESCENCE : not significant
  • IDENTIFYING VISUAL CHARACTERISTICS : fiberous inclusions, parallel tubes, fingerprint pattern (liquid filled) inclusions and 2-phase (liquid and gas) inclusions.

5) WHITE TOPAZ

Present Sources Brazil, Sri Lanka, Africa, Mexico and U.S.A.

Gemological Characteristics
  • SPECIES : topaz
  • TRANSPARENCY : transparent
  • COLOR : white (colorless)
  • REFRACTIVE INDEX : 1.619 - 1.627
  • BIREFRINGENCE : .008
  • PLEOCHROISM : weak to strong dichroism and trichroism
  • CRYSTAL SYSTEM : orthorhombic
  • OPTIC CHARACTER : doubly refractive
  • SPECIFIC GRAVITY : 3.52 MOHS
  • HARDNESS : .014
  • FLUORESCENCE : long wave - inert to weak yellow
  • IDENTIFYING VISUAL CHARACTERISTICS : liquid/gas and other natural inclusions, basel cleavage, possible 3-phase inclusions, and "rhombic" (four sided) etch markings.

Gemstones of Ketu


1) CAT'S EYE

Present Sources Sri Lanka, Brazil, South India, and Burma.

Gemological Characteristics
  • SPECIES : chrysoberyl
  • TRANSPARENCY : transparent to translucent
  • COLOR : yellow, greenish-yellow, brownish- yellow,
  • REFRACTIVE INDEX : 1.746 - 1.755
  • BIREFRINGENCE : .009
  • PLEOCHROISM : weak to strong dichroism to trichroism
  • CRYSTAL SYSTEM : orthorhombic
  • OPTIC CHARACTER : doubly refractive
  • SPECIFIC GRAVITY : 3.73 MOHS
  • HARDNESS : 8 1/2
  • DISPERSION : 0.015
  • FLUORESCENCE : nil
  • IDENTIFYING VISUAL CHARACTERISTICS : strong chatoyant "cat's-eye" looking light band caused by light reflection on minute included crystal fibers or tubes, also natural and fingerprint inclusions.

2) APATITE CAT'S EYE

Present Sources Sri Lanka, Burma, Bohemia, Mexico, Maine (USA), and other sources.

Gemological Characteristics
  • SPECIES : apatite
  • TRANSPARENCY : transparent to translucent
  • COLOR : yellow, yellow-green, green, gray- green, brownish-green/yellow
  • REFRACTIVE INDEX : 1.642 - 1.646
  • BIREFRINGENCE : .002 - .006
  • PLEOCHROISM : weak to strong dichroism
  • CRYSTAL SYSTEM : hexagonal
  • OPTIC CHARACTER : doubly refractive
  • SPECIFIC GRAVITY : 3.18 MOHS
  • HARDNESS : 5
  • DISPERSION : .013
  • FLUORESCENCE : long wave--moderate yellowish/dark greenish, short wave--weak yellowish/ dark greenish; long/short wave-inert to moderate light pinkish
  • IDENTIFYING VISUAL CHARACTERISTICS : similar to chrysoberyl and tourmaline cat's-eyes except for lower properties.

3) TOURMALINE CAT'S EYE

Present Sources Sri Lanka, Burma, South West Africa, Ural Mountains (Russia), Brazil, Madagascar, Maine and California (USA).

Gemological Characteristics
  • SPECIES : tourmaline
  • TRANSPARENCY : transparent to translucent
  • COLOR : chrome-green, yellow-green, blue-green, brownish-green
  • REFRACTIVE INDEX : 1.62 - 1.64
  • BIREFRINGENCE : .020
  • PLEOCHROISM : strong dichroism
  • CRYSTAL SYSTEM : hexagonal
  • OPTIC CHARACTER : doubly refractive
  • SPECIFIC GRAVITY : 3.06 MOHS
  • HARDNESS : 7 - 7 1/2
  • DISPERSION : .017
  • FLUORESCENCE : not significant
  • IDENTIFYING VISUAL CHARACTERISTICS : color zoning, natural inclusions, e.g., threadlike liquid and gas inclusions, with chatoyant "cat's-eye" effect.

Gemstones of Saturn

1) BLUE SAPPHIRE

Present Sources Burma, Sri Lanka, Thailand & Cambodia

Gemological Characteristics
  • SPECIES : corundum
  • TRANSPARENCY : transparent to translucent
  • COLOR : blue, violetish-blue, greenish-blue, blackish- blue, gray blue, purple and violet
  • REFRACTIVE INDEX : 1.762 - 1.770
  • BIREFRINGENCE : .008
  • PLEOCHROISM : strong dichroism
  • CRYSTAL SYSTEM : hexagonal
  • OPTIC CHARACTER : doubly refractive
  • SPECIFIC GRAVITY : 4 MOHS
  • HARDNESS : 9
  • DISPERSION : 0.018
  • FLUORESCENCE : light blue sapphire--moderate to strong pink (long wave), purple/violet sapphire--inert to strong reddish violet (long wave) and inert to moderate reddish (short wave)
  • IDENTIFYING VISUAL CHARACTERISTICS : fingerprint inclusions, hexagonal growth lines, silk (rutile) and straight color banding.

2) TANZANITE

Present Sources Tanzania (Africa)

Gemological Characteristics
  • SPECIES : zoisite
  • TRANSPARENCY : transparent
  • COLOR : blue, violetish-blue
  • REFRACTIVE INDEX : 1.691 - 1.704
  • BIREFRINGENCE : .013
  • PLEOCHROISM : weak to strong dichroism
  • CRYSTAL SYSTEM : orthorhombic
  • OPTIC CHARACTER : doubly refractive
  • SPECIFIC GRAVITY : 3.30 MOHS
  • HARDNESS : 6 - 7
  • DISPERSION : .021
  • FLUORESCENCE : not significant
  • IDENTIFYING VISUAL CHARACTERISTICS : strong blue and violet pleochroism.

NOTE: As tanzanite is usually heat-enhanced we do not whole-heartedly recommended it for astrological use.

3) BLUE SPINEL

Present Sources Burma, Thailand and Sri Lanka

Gemological Characteristics
  • SPECIES : spinel
  • TRANSPARENCY : transparent
  • COLOR : blue, violet-blue and purplish-blue
  • REFRACTIVE INDEX : 1.718
  • CRYSTAL SYSTEM : cubic
  • OPTIC CHARACTER : singly refractive
  • SPECIFIC GRAVITY : 3.60 MOHS
  • HARDNESS : 8
  • DISPERSION : .020
  • FLUORESCENCE : not significant
  • IDENTIFYING VISUAL CHARACTERISTICS : natural inclusions, e.g., needles, spinel octahedral crystals (often in fingerprint pattern), and iron oxide inclusions.

4) AMETHYST

Present Sources Brazil, Ural Mountains (Russia), Uruguay, Arizona (USA) and to some extent in almost every part of the world.

Gemological Characteristics
  • SPECIES : quartz
  • TRANSPARENCY : transparent
  • COLOR : purple
  • REFRACTIVE INDEX : 1.544 - 1.553
  • BIREFRINGENCE : .009
  • PLEOCHROISM : weak to strong dichroism
  • CRYSTAL SYSTEM : hexagonal
  • OPTIC CHARACTER : doubly refractive
  • SPECIFIC GRAVITY : 2.66 MOHS
  • HARDNESS : 7
  • DISPERSION : .013
  • FLUORESCENCE : not significant
  • IDENTIFYING VISUAL CHARACTERISTICS : vitreous conchoidal fracture, liquid inclusions, 2-phase inclusions, negative crystals, color zoning or banding, and uneven coloration.

Gemstones ofMars

1) CORAL

Present Sources Mediterranean Sea, Red Sea, Persian Gulf, and the coasts of Algeria, Tunisia, Taiwan, Spain, Italy, Japan and Australia.

Gemological Characteristics
  • SPECIES : coral
  • TRANSPARENCY : translucent
  • COLOR : red, pink, reddish-orange & orange
  • REFRACTIVE INDEX : 1.486 - 1.658
  • CRYSTAL SYSTEM : aggregate
  • SPECIFIC GRAVITY : 2.65 MOHS
  • HARDNESS : 3 1/2 - 4
  • DISPERSION : .038
  • FLUORESCENCE : n/a
  • IDENTIFYING VISUAL CHARACTERISTICS : wavy parallel fibrous structure, uneven fracture with dull luster.

2) CARNELIAN

Present Sources Brazil, India, Uruguay and many other places.

Gemological Characteristics
  • SPECIES : chalcedony
  • TRANSPARENCY : transparent - semi-translucent
  • COLOR : red, orange-red, brownish-red, or brownish-orange
  • REFRACTIVE INDEX : 1.535 - 1.539
  • CRYSTAL SYSTEM : hexagonal
  • OPTIC CHARACTER : aggregate
  • SPECIFIC GRAVITY : 2.60 MOHS
  • HARDNESS : 6 1/2 - 7
  • FLUORESCENCE : not significant
  • IDENTIFYING VISUAL CHARACTERISTICS : dull to waxy conchoidal fracture.

3) BLOODSTONE

Present Sources Brazil, India, Uruguay and many other places.

Gemological Characteristics
  • SPECIES : chalcedony
  • TRANSPARENCY : translucent - semi-translucent
  • COLOR : red, orange-red, brownish-red, or brownish-orange
  • REFRACTIVE INDEX : 1.535 - 1.539
  • CRYSTAL SYSTEM : hexagonal
  • OPTIC CHARACTER : aggregate
  • SPECIFIC GRAVITY : 2.60 MOHS
  • HARDNESS : 6 1/2 - 7
  • FLUORESCENCE : not significant
  • IDENTIFYING VISUAL CHARACTERISTICS : conchoidal fracture with dull to waxy luster on the fracture surface, distinguishing it from glass, There are no substitutes which imitate bloodstone closely.

With all the above information at hand, anyone can determine which sort of gemstone best suits his or her astrological requirements, then refer to the scientific gemological data for proper identification of the gemstone(s) of choice. When choosing gems for astro-therapy, it is always best to first consult a qualified sidereal astrologer in order to correctly cast one's individual horoscope according to the ancient but highly accurate Vedic system of India. And when purchasing astrologically potent gems, one should deal exclusively with reputable suppliers and be prepared to pay (in some cases) fairly steep prices. Only flawless gems transmit positive energies from the planets to the wearer, and flawless gems are usually rare and can be expensive. It's far better to wear no gems at all than to wear flawed, inexpensive ones, because inferior specimens not only fail to transmit positive energies, they actually attract negative influences

In order to provide the reader with some clear cut insights regarding the practical personal use of astrologically potent gems, the following chapter gives concrete examples of how various types of stones may be employed to offset and counterbalance unfavorable astrological influences in a person's life. All of these anecdotes are drawn from actual cases known to the author or recorded in authenticated texts.

Ancient Astrological Gemstones & Talismans index, Astral Gemstone Talismans main directory.
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