SC - Gemstonesy

[david friedman]

At 2:22 PM -0400 10/9/00, Jenne Heise wrote:
>  > >>>  A further consideration is that something labelled "synthetic X" may
>>  >>>  actually be "synthetic Y in a color that looks like X." Many
>>  >>>  synthetic gemstones are either corundum or spinel, colored to match
>>  >>>  whatever they are supposed to be.
>
>Part of that is because a proportion of gemstones ARE corundum (rubies,
>sapphires etc)

I don't think there is any cetera to be et there--in modern usage, 
any gem corundum that isn't red is a sapphire. My point was that 
corundum and spinel, being easy to synthesize, are used to provide 
imitations of things that are not corundum or spinel--emerald, 
amethyst, etc.

>classified by the color they are. :) Furthermore, the
>situation in period was even more murky: Red spinel would in fact be a
>period 'ruby' as they didn't have the same sophisticated classification
>schemes and tests we do: hence 'The Black Prince's Ruby', which is a
>spinel.

For which the period term was "ballas ruby" as distinguished from "ruby."

>I would suspect that for our purposes, if the synthetic process resembles
>the process by which the gem is created in nature, it is probably a
>reasonable substitute: cultured pearls for pearls, etc. Since we aren't
>practicing the same kind of symbolic magick based on value the original
>users did, having the same chemical make-up ought to be enough.

I was assuming, in my responses, the point of view of someone who 
took the recipe seriously, hence regarded the relevant medical 
beliefs as a science he didn't understand very well rather than (as I 
actually regard them) superstition that can be ignored for practical 
purposes.

Once you abandon that assumption, why do you care about the chemical 
make-up? Why not use colored glass for everything?

>
>An excellent period work on gemstones available in translation from
>Scarecrow Press is:
>_Arab Roots of Gemology: Ahmad ibn Yusuf Al Tifaschi's Best Thoughts on
>the Best of Stones_ Samir Najm Abul Huda. Scarecrow Press, 1997. $45.00.
>ISBN:0-8108-3294-1

It's certainly an interesting book, but a rather specialized one, 
since it is the translation of a particular Arabic lapidary.
- -- 
David/Cariadoc
http://www.daviddfriedman.com/