rock or stone

[steve f]

I recently inherited a whole lot of equipment and opal from a man that has passed away ( Flemming Jensen ) the older members may know him
I have posted some pictures in the gallery on something he was working on
I dont know what it is and have labelled the photos as glass or rock, if anyone has a clue, let me know please

[Rusted]

Your photos are a bit blurry and a bit dark but to me it looks like slag glass.

[RoughCreations]

Yes, that was my initial reaction too without a sharper zoomed-in image.

[Bucket]

Hi Steve, I tend to agree with the others, clearer, well lit photos would help. However, I'm going out on a limb here and saying there may be a couple of opals there, maybe volcanic rather than seam opal. The ones in photos 2 and 3 look like they may have a little bluish potch showing, but I can't tell with being able to zoom in a bit more.

[steve f]

I have changed the blurry pictures for hopefully clearer ones

[RoughCreations]

I have changed the blurry pictures for hopefully clearer ones

That's better. Looks very much like a form of cryptocrystalline silica. I am still thinking it's man-made. Looks a bit like https://www.detektorweb.info/clanek/kaminek which is a glass remnant from a Czech glass-making furnace.
RC

[steve f]

RC
your right, tested as glass with a presidium thermal conductivity tester

[RoughCreations]

The next question is whether the late Mr Jensen ever travelled to the Czech Republic...

[steve f]

No he hadn't, he had the butcher shop at coober pedy for years

[Jimnyjerry]

opal mining areas tend to have a mix from the United Nations, so he could have had a few Czech  customers.