MicrobeHunter.com Microscopy Forum

This is the surface of a pulled synthetic sapphire surface. Looks a bit like a cephalopod of sorts....

That is astonishing !!
A product that we like to think is one of Mankind’s closest approaches to perfection, revealed.

Can you share any more detail of the specimen ?

MichaelG.
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Edit: Here’s some brief background notes about synthetics:
https://www.gia.edu/gem-synthetic
... Must investigate further.

Really nice! I'd like to see more images of gems and minerals.

This produced with epi-DIC and a full-wave plate? What objective did you use here?

Interesting. Like to see more along those lines.

Great image - thanks. Add me to the chorus of those curious to learn more.

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A look at Wiki provides a surprising (to me anyway) potential source of Synthetic sapphire if anyone wanted to get their mittens on some:

"... Sapphire-glass windows are used in both high pressure and vacuum chambers for spectroscopy, crystals in various watches, and windows in grocery store barcode scanners since the material's exceptional hardness and toughness makes it very resistant to scratching."

Hands up - give me the glass of your scanner!

I was initially doubtful ... but this corroborates the Wikipedia claim:

The performance of EVERSCAN is similar to sapphire scanner windows at a fraction of the price. Unlike sapphire windows, however, EVERSCAN can be produced in any size to meet the demands of new system designers or to replace scanner glass in existing scanners. DIAMONEX can provide this product in quantities suitable for scanner equipment manufacturers or grocery store chains.

https://www.azom.com/article.aspx?ArticleID=3637

... We need to target the right stores, Bob

MichaelG.

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Edit: https://global.kyocera.com/prdct/fc/lis ... index.html

MichaelG. wrote: ↑

Fri Mar 13, 2020 5:47 am

That is astonishing !!
A product that we like to think is one of Mankind’s closest approaches to perfection, revealed.

Can you share any more detail of the specimen ?



MichaelG.
.

Edit: Here’s some brief background notes about synthetics:
https://www.gia.edu/gem-synthetic
... Must investigate further.

This is the rough surface of a pulled sapphire. Pulling is a growth process where there is a crucible of alumina melt. A feed crystal is lowered into contact with the melt and slowly pulled upward as the crystal grows onto the seed getting larger and much longer. That’s the short answer anyway. The squid “eye” is a small iridium contaminant from the crucible lining and is the cause of the irregular shape on the surface that looks like a squid.

Wes wrote: ↑

Sat Mar 14, 2020 7:48 am

Really nice! I'd like to see more images of gems and minerals.

This produced with epi-DIC and a full-wave plate? What objective did you use here?

This is only epi DIC. No wave plate was used...actually still looking to find a wave plate for my Zeiss.

Microworldofgems wrote: ↑

Sun Mar 15, 2020 5:33 pm

Wes wrote: ↑

Sat Mar 14, 2020 7:48 am

Really nice! I'd like to see more images of gems and minerals.

This produced with epi-DIC and a full-wave plate? What objective did you use here?

This is only epi DIC. No wave plate was used...actually still looking to find a wave plate for my Zeiss.

So the first-order colors are produced by the DIC prism alone? Which condenser type and reflector did you use?

Microworldofgems wrote: ↑

Sun Mar 15, 2020 5:32 pm

The squid “eye” is a small iridium contaminant from the crucible lining and is the cause of the irregular shape on the surface that looks like a squid.

Thanks ... That's the bit that was puzzling me.

MichaelG.

Wes wrote: ↑

Sun Mar 15, 2020 6:48 pm

Microworldofgems wrote: ↑

Sun Mar 15, 2020 5:33 pm

Wes wrote: ↑

Sat Mar 14, 2020 7:48 am

Really nice! I'd like to see more images of gems and minerals.

This produced with epi-DIC and a full-wave plate? What objective did you use here?

This is only epi DIC. No wave plate was used...actually still looking to find a wave plate for my Zeiss.

So the first-order colors are produced by the DIC prism alone? Which condenser type and reflector did you use?

Correct, the DIC prism produces the vibrant colors or gray scale image depending on the position of the prism over the objective. Also, there is no condenser used for epi-DIC. The objective lens acts as the condenser using a vertical illuminator to reflect light off of the surface through the objective and the light bounces off the surface back through the same DIC prism. Only one DIC prism is required for epi-DIC using this arrangement.