APATITE. Apatite is a mineral which obtained its name from the Greek word APATAO, to deceive, because it deceived old students who confounded it with aquamarine, chrysolite, tourmaline, etc. Abraham Werner (the author of the Neptunian theory that all mineral substances were once contained in watery solution), first demonstrated in the 18th century the true nature of apatite which is a phosphate of lime with fluorite and chloride of calcium. The lustre varies from transparent to opaque, and is vitreous to sub-resinous. It is much softer than tourmaline, its degree of hardness being but 5; for this reason it is but little used in the manufacture of jewellery. Its colours are pale sea-green, blue-green (in which colouring it is sometimes called Moroxite), yellowish-green (in which colouring it is often called Asparagus stone), yellow, violet, white, grey, brown, red, colourless, and transparent. Professor Judd, F.R.S., found a concretion specimen of apatite when cutting a mass of teak wood—a particularly rare find. In agreement with the ancient system the apatite is astrologically under the zodiacal Pisces.
APOPHYLLITE. Apophyllite is a hydrous silicate of potassium and calcium which obtains its name from the Greek word APOPHULLIZO, to exfoliate, because it falls in leaves before the blowpipe. It is extremely soft, being from between 4 and 5 in Mohs’s scale. The stone is found in a variety of colours—milk-white, greyish, green, yellow, red, pink. It is seldom used by jewellers. The apophyllite is under the sign Taurus.
AQUAMARINE. (See [BERYL].)
ASBESTOS. The word is derived from the Greek ASBESTOS, inconsumable, and is identified with the Amianthus (impollutible) of the ancients. It is a variety of hornblende, of a fine and fibrous texture, of which Marbodus wrote:
“Kindled once it no extinction knows
But with eternal flame increasing glows.
Hence with good cause the Greeks Asbestos name,
Because once kindled nought can quench its flame.”
The incombustibility and weak heat conducting qualities of asbestos render it extremely useful as a protection against fire. The ancients used it for the wicks of their temple lamps, and in order to preserve the ashes of the departed their dead bodies were laid on asbestos before being placed on the funeral pyre. Cloths of asbestos were thrown in the flames for the purpose of cleaning them. So fine and flaxy is the mineral that gloves have been made of it. Asbestos is under the zodiacal Gemini.
AVENTURINE. Aventurine or goldstone is a quartz of a brownish, semi-transparent character, spangled with spots of golden-yellow mica. This stone is identified with the stone called by Pliny the “Sandaresus”—“of stars of gold gleaming from within.” The name Aventurine (per adventura, by accident), arose, it is said, from an accident in a Venetian glass factory, where a workman found that eight parts of ground glass, one part protoxide of copper and two parts of oxide of iron well heated and allowed to cool slowly, produced the peculiar appearance admired in the real gem to even better effect. The aventurine variety of quartz is under the zodiacal Leo.