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[ALshawani]

Hello everyone, I want help identifying this stone, knowing that it scratches the agate

[Sante Celiberti]

Hello.

If you cannot test the hardness, try testing the gravity.
On such a homogeneous material it should not be difficult.
The hexagonal prismatic habit is a further indication.
An -at least approximate- locality would be helpful.

Best wishes.

[ALshawani]

Welcome
Thank you for replying
In terms of hardness, I tried scratching the agate and it was easily scratched, which means that the hardness is above 7. In terms of location, it is North Africa, northwest of Libya.

[Sante Celiberti]

Beryl?

Habit, lustre, colour could fit.
But, with no further tests, just a guess...

[Bob Morgan]

Perhaps this is Libyan Desert glass. But I don't think such is as hard as agate.

[Matt_Zukowski]

I don't see any reason to assume that these rocks are mono-mineralic. It looks like some sort of clastic rock or corroded igneous rock with a coating of cryptocrystaline quartz on one side. I am not sure that the hardness really is >7; hardness tests can be hard to interpret with anything close to friable or with materials of similar hardness. I would be doubtful if you can get anything definitive from us with the information provided. I recommend that you find a geology club, or better a geology department of a nearby university, to identify what you have.

Good luck.

[lluis]

Just a guess from what Matt said before...
Maybe lechatelierite (fused sand by a lightning)?
Seems that there is some hole, and that are tubes of fused sand recovered with original sand... That could may scratch chalcedony (the surrounding sand, I mean)
Just quartz may look that scratches quartz...

Hope it serves

Lluís

[James Catmur]

Agate is not as hard as quartz, so assume >6.5

[lluis]

Then, lechatelierite coated by sand (quartz) would fit perfectly with scratching and shape...

Lluís

[Sante Celiberti]

Lechatelierite seems to be the most likely identification, although I'm unable to reconcile the apparent and frequent hexagonal prismatic habit with the amorphous structure of Libyan dessert glass.

[James Catmur]

Given it is uniform and you have a lot of this material the specific gravity should be easy to determine using this method

https://www.mineral-forum.com/message-board/viewtopic.php?p=46342#46342

[lluis]

Ciao, Santi

Maybe I am wrong, but Libyan glass is due to an impact and lechatelierite is due to electricity.
Not same in origin, although all being at end fused quartz...
Lechatelierite is roundish, and use to have a hole in any place. As I see in this case.
I fail to see hexagonal shapes (maybe forcing my slight imagination.....). But cylindrical fits more with my mental schemes... Maybe sorry, but is what I see..

With best wishes

Lluís

[Sante Celiberti]

Ciao, LLuis.

Of course, the cylindrical shape, common in these stuffs, is evident.
Nonetheless, I seem to see, amongst the shown material, at list three pieces with a coarse hexagonal shape. The same I seem to see in 1st and 7th photo on Mindat (Lechatelierite).
But perhaps this is due to my imagination or, more likely, to my maculoopathy.

Warm greetings.

[ALshawani]

Such as what tests are required

[ALshawani]