Crystal and stones » chrysolite

History of birthstones

precious stones — Tue, 22 Jun 2010 21:27:19 +0000

The historian Josephus proclaimed a connection between the twelve stones in Aaron’s breastplate, the twelve months of the year and the twelve signs of the zodiac. The Breastplate of Aaron, referred to in Exodus 28:17-20:

10 Then they mounted four rows of precious stones on it. In the first row there was a ruby, [...]

Topaz

precious stones — Wed, 16 Sep 2009 15:57:38 +0000

The name topaz is derived from the Greek topazos, which is the name of a small island situated in the Gulf of Arabia, from whence the Romans obtained a mineral which they called topazos and topazion, which mineral to-day is termed chrysolite.

The mineral topaz is found in Cornwall and in the British Isles [...]

Sapphire

precious stones — Wed, 16 Sep 2009 15:48:37 +0000

The Sapphire is not so easy to imitate, as its hardness exceeds that of the ruby, and imitations containing its known constituents, or of glass, are invariably softer than the natural stone.

As before remarked, almost any form of corundum other than red is, broadly, called sapphire, but giving them their strictly correct designations, [...]

Green gemstones

precious stones — Wed, 16 Sep 2009 15:20:47 +0000

Green gemstones

Hardness. Specific Gravity.

Aquamarine 7-3/4 2.701-2.800 Chrysoberyl 8-1/2 3.689-3.752 Chrysolite 6-7 3.316-3.528 Chrysoprase (Quartz) 7 2.670 Diamond 10 3.502-3.564 Dioptase 5 3.289 Emerald and Oriental Emerald 7-3/4 2.690 Euclase 7-1/2 3.090 Garnet (see also Red Garnet) 6-1/2-7-1/2 3.400-4.500 Heliotrope (Chalcedony) 6-1/2 2.598-2.610 Hiddenite (a variety of Spodumene) 6-1/2-7 3.130-3.200 Jade 7 [...]

Yellow Stones

precious stones — Wed, 16 Sep 2009 15:02:53 +0000

Yellow Stones

Hardness. Specific Gravity.

Amber 2-1/2 1.000 Beryl 7-3/4 2.709-2.810 Chrysoberyl 8-1/2 3.689-3.752 Chrysolite 6-7 3.316-3.528 Corundum (the yellow variety known as “Oriental Topaz”) 9 3.90-4.16 Diamond 10 3.502-3.564 Garnets (various) 6-1/2-7-1/2 3.4-4.5 Hyacinth (a form of Zircon) 7-1/2 4.7-4.88 Quartz (Citrine) 7 2.658 Sapphire 9 4.049-4.060 Spinel 8 .614-3.654 Topaz (for “Oriental [...]

Rhodonite to Nephrite

precious stones — Wed, 16 Sep 2009 14:15:37 +0000

Group D. -Stones whose specific gravity lies between 3 and under 3.50.

Rhodonite 3.413 and occasionally to 3.617 Garnets 3.400 ” 4.500 Epidote 3.360 ” 3.480 Sphene 3.348 and occasionally to 3.420 Idocrase 3.346 ” 3.410 Olivine 3.334 ” 3.368 Chrysolite 3.316 ” 3.528 Jade 3.300 ” 3.381 Jadeite 3.299 Axinite 3.295 Dioptase 3.289 Diopside [...]

Specific gravity of gemstones

precious stones — Wed, 16 Sep 2009 13:53:09 +0000

The fixing of the specific gravity of a stone also determines its group position with regard to weight; its colour and other characteristics defining the actual stone.

This is a safe and very common method of proving a stone, since its specific gravity does not vary more than a point or so in different [...]

Origin of precious stones

precious stones — Wed, 16 Sep 2009 12:45:01 +0000

Though the origin, formation, composition, characteristics and tests of each stone will be examined in detail when dealing with the stones seriatim, it is necessary to enquire into those particulars of origin which are common to all, in order thoroughly to understand why they differ from other non-metallic and metallic minerals.

At the very commencement [...]