It's been a busy couple months but we have a gem show in town this week and I picked up some opals. This one has a protrusion of rhyolite matrix with opal or chalcedony growing on it, resemvbling a fort on a hill.
It is fun material with a lot of color and interesting inclusions, but it has to be kept wet to the point of using a water dropper on it while I shot the stacks. The FoV is 11mm across, really more macro in magnification but I shot it with my 2x thorlabs objective on my microscope.
I might revisit this one. Lighting opal is really challenging and having to constantly rewet it added to it. I should probabably try with my Z6 at a lower NA since the surface is not perfectly flat.
Fortress in opal
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Re: Fortress in opal
Very pretty!
I'm curious about the continuous wetting with water. Is that to avoid any possible contamination of the stone by liquids that would not evaporate?
--Rik
I'm curious about the continuous wetting with water. Is that to avoid any possible contamination of the stone by liquids that would not evaporate?
--Rik
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Re: Fortress in opal
If it dries out too much it will crack, and between the dry air and fiber optic lights it starts to dry out pretty fast. There are also some preexisting minor cracks and scratches that wetting effectively obscures (the scratches could probably be polished out, though I am not certain how this material will hold up to grinding and final polish--it would probably need hand polishing).
Re: Fortress in opal
Lovely. Could you put it under a thin layer of water?
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Re: Fortress in opal
Absolutely, and it might be a better solution. It just comes with some logistical issues of its own--ie mineral tack doesn't stick well when it's even damp so I'd need a diffetent solution to pose it underwater. Maybe if I made a well around the area of interest I could keep a thicker film going. Or maybe glycerine would be better--I am definitely thinking of it for long term display since it won't tend to get cloudy.
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Re: Fortress in opal
Its reminiscent of those grow at home crystal kits we had as kids. Its really beautiful.
-- Bob
-- Bob