Quince - 29-4-2005 at 00:52
What's the cheapest source of artificial sapphire? I need thin, not necessarily polished, rectangular pieces, on the order of half mm thick,
grade no worse than 4. I need a very small amount -- that I can cut up into ten rectangles; the rectangles' size is min 4x6 max 5x10 mm.
I'd also like to know how to cut it, and how to drill half mm holes in it. Cheapest I found this far would cost me about $100, and I'd have
to cut it myself 
[Edited on 29-4-2005 by Quince]
neutrino - 29-4-2005 at 02:20
Have you tried finding a company with the Thomas Register? Also, try Froogle, that’s how I found the company I buy most of my labware from.
uber luminal - 29-4-2005 at 10:07
If you just need it for its surface...
sapphire/ruby, aka Corundum aka Al2O3 which is found on every piece of clean Al that has been exposed to O2...
Otherwise, you will probably want them precut, since corundum's hardness(9) is pretty close to Diamond(10).
hardended steel is around 5.5 and good tool steel is around 7. (by Mohs hardness scale). According the Mohs, you would need a diamond saw to cut
corundum. (However there are other materials out there that would do the job too)
if they were thin, you could try to break it apart, but I dont think corundum can be easily fractured(evenly).
You could try placing the 2 sides into clamps/vise and using a hammer shock one side to get a pretty even fracture. its not like you can score the
corundum... unless you have a diamond 
**edit, ok, 9 isnt close to 10 on the Mohs scale, but since the scale is practicaly exponential, 9 is much closer to 10 than anything else.
[Edited on 29-4-2005 by uber luminal]
12AX7 - 29-4-2005 at 11:31
A carbide or diamond glass scoring tool would probably cut it (HA! HA!), followed by a quick, if tough, snap and you're done. (Mind you,
it's a whole lot stronger than ordinary glass.)
So yeah...find someone dealing in that and see if you can get some thin enough.
Tim
Quince - 29-4-2005 at 15:25
How do I drill a half mm hole in it? The smallest diamond rotary tool tip I found at the hardware stores is 1.5 mm.
uber luminal - 29-4-2005 at 16:13
make the hole with something besides abrasive working?
12AX7 - 29-4-2005 at 19:14
Like I said in the U2U. Acoustic drilling can do this. No, not something you're going to do at home. Single crystal saphire isn't,
either.
Tim
Quince - 29-4-2005 at 20:35
Could a jeweller drill it? I know that watch repair people for example can deal with sapphire, since expensive watches often use sapphire windows.
I got one quote for the sapphire, but it would cost me $100 for what I need, as they don't usually deal in small quantities. I'm hoping to
find for half that.
[Edited on 30-4-2005 by Quince]
Madandcrazy - 16-5-2005 at 06:51
A good jeweller drill the crude saphires
into a form and the price is rising, although the weight is sinking.
Many froud is of the internatinal market.
- imitatings
- low quality (air-involvements)
- synthetical stone 
Someone can take you a mess with
a low priced tender.
Twospoons - 16-5-2005 at 23:08
Cutting and drilling might be done with a chemical etch, and suitable masking of the saphire. Doesn't alumina dissolve in NaOH ?
Edmund Scientific sell saphire windows, though they're round. 6mm diameter x 0.5 thick goes for about $48, so I guess thats a bit pricey.
Quince - 16-5-2005 at 23:53
Damn. Thank goodness for free samples.
neutrino - 17-5-2005 at 02:04
Edmund Scientific? You definitely don’t want to be buying from them. The scientific supplies are horridly expensive and the optics are meant for
professionals with <i>very</i> deep pockets.
Madandcrazy - 17-5-2005 at 06:26
Edmund Scientific ?
What have Edmund Scientific to do with optics and dissolved aluminum in NaOH ?
A good jeweller have modern optic to consider the stones.
I don`t think, aluminia can be dissolved good in hot NaOH solution.
12AX7 - 17-5-2005 at 07:09
2NaOH + Al2O3 = 2NaAlO2 + H2O
Not sure if it works on bulk material or just hydrated stuff though...(would probably etch it at least). At any rate the above (driven by heating and
cooling) is the Bayer process for purifying alumina for smelting to metal (among other uses).
Tim
neutrino - 17-5-2005 at 12:49
Edmund split into two sections at some time in the past--a scientific supplier and a high-end optics manufacturer.