Not of Vegetable Origin

My previous post made me think, "What's -not- of vegetable origin, then?" The answer seems obvious, but not entirely so.

Metals are mostly not extracted from plants, although it's possible to do it. Ceramics are mostly aluminosilicate clays; glasses are only of vegetable origin insofar as they contain sodium or potassium carbonate. Other crystalline minerals normally have the vegetable components burnt or reacted out of them during the formation process — sapphire, jade, diamonds and such.

But diamonds were once coal, and coal is of vegetable origin. Marble was once limestone, which was once the exoskeletal remains of shellfish and such — and those, one presume, consumed vegetation at some point. It's hard to escape from plants — they're the main convertors of energy and raw materials into the substances everything else needs.

Crystallomancy

So... what do you have to know in order to earn a diploma in gemology? I did some research. The results were pretty uniform. Here is a sample from the British Gemological Association's traditional list, comprising 31 syllabus sections.

1. Gem Materials

Nature and attributes of gems and ornamental materials; factors which influence the value of a stone: beauty, durability, rarity; acceptability. Earth’s physical activity; melting, recrystallization, sedimentation, mineralization.

2. The Nature of Gem Materials

The origin and occurrence of gem minerals (elementary). Major types of gem deposit (general description): pegmatite; diamond pipe; placer; hydrothermal vein. Extraction: mining and recovery methods (outline only). Minerals, atoms, elements and chemical bonding (elementary).

...

6. The Nature of Light

The importance of light in gemmology. The nature of light. Wavelength and frequency. The electromagnetic spectrum. The visible spectrum of colour. Polarization and vibration direction.

7. Refraction

Refraction; refractive index (RI), definition and description. Singly refractive materials. Doubly refractive materials: directional properties; double refraction, polarization, optic axes. Measurement of RI; the refractometer; the principle of total internal reflection; an outline of its main component parts. The determination of birefringence using the refractometer.

8. Reflection and its Effects

External reflection: lustre. Examples of lustre. Internal reflection effects caused by inclusions; chatoyancy and asterism. Internal reflection effects caused by structural features. Iridescence: interference and diffraction. Brilliance.

...

15. Artificial Gem Materials

Artificial and synthetic gems: definitions. A brief outline of methods of production and identification of materials produced by the Verneuil flame fusion, flux melt and hydrothermal methods. Non-crystalline artificial materials: paste; plastics.

16. Imitation and Composite Gem Materials

Imitation (simulation) of gem and ornamental materials; the use of natural and artificial materials as imitations; the distinction of gem diamond from its simulants, particularly cubic zirconia (CZ). Composite (assembled) natural and artificial stones; reconstructed materials.

...

21. Structure and Properties of Gem Materials

Atomic-scale structure, electrons and chemical bonding. The crystalline state and crystalline materials. Crystal structures in terms of chemical bonding. Structural isomorphism: ‘isomorphous substitution’. Crystalline polymorphism. The relationship of crystal structure and symmetry to crystal faces, forms, habits, cleavage, internal growth phenomena and crystal surface markings; relevance to identification.

...

31. Description of Gem Materials of Organic Origin

Origin, occurrence, recovery, methods of identification and common simulants of: amber, copal, coral, ivory, jet, tortoiseshell; pearls — natural, cultured (nucleated and non-nucleated), marine and freshwater; shell (particularly as used for cameos and as mother-of-pearl).

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It is the kind of thing that would be wonderfully rewarding for high school seniors (or junior acolytes in Atlantean Shrines of the Book) to be studying. 'Instead' of science, I suppose.

A Brief History Of Some Rock

Well, here I am back from the Bay of Bengal, the tsunami amplifier of the region. On a clear day you think you can see forever, but what you are seeing is inestimable beauty mixed with a poverty that is induced by the globalisation of a certain kind of wealth-concept.

Because certain people over the globalisation history of the last 200 years have successfully imposed certain wealth values on others, to their own benefit, those others have become poorer. Sri Lanka, the Ceylonese centre of great wealth and marvellous gems; the various city-states of the Indian sub-continent; the mysterious outskirts of Indochina... all of these have been exploited to their own detriment by the powers of the world, minor pieces and pawns in the Great Game.

Why else are gems mined in this region marked up 10x in their journey to the markets of Bangkok, marked up 10x again en route to Hongkong, and 10x again as they fly their clattering journey to London? The miners are as poor as dirt; the dirt is perhaps richer. The society belles with the outsize carbon and impure alumina and other Mammon-sanctified rocks — they live on the backs of the poor. And why ever should this have come to pass? These aren't even useful rocks in their shiny metal cages.

I sat by the Bay of Bengal. And I laughed, and the waters answered me.