Sciencemadness Discussion Board

beryllium oxide vs aluminum oxide

Eric Slighton - 29-10-2016 at 18:53

Does anyone know a test that would distinguish one from the other?

Metacelsus - 29-10-2016 at 19:59

An easy way to tell them apart would be by density (if you have enough material). Beryllium oxide is 3.01 g/mL and aluminum oxide is 3.95 g/mL.

Eric Slighton - 29-10-2016 at 20:32

Hmm... It is in an assembly & hard to take out.

j_sum1 - 29-10-2016 at 21:03

I assume you are looking at gemstones -- essentially looking at the difference between beryl/emerald/aquamarine and rubies

A hardness test might help. But if that is your context I would consider getting it appraised by an expert. The crystal structures are different (trigonal vs hexagonal). Refractive index and birefringent properties also differ. But I doubt there is anything really simple that you could do to tell them apart.

unionised - 30-10-2016 at 02:14

Topaz should be harder than beryllium oxide, but less hard than alumina.

Why do you want to know? Is it an electrical insulator?

Metacelsus - 30-10-2016 at 05:23

Quote: Originally posted by j_sum1  
I assume you are looking at gemstones -- essentially looking at the difference between beryl/emerald/aquamarine and rubies.


Beryl isn't beryllium oxide. It's a beryllium aluminum silicate (as are emerald and aquamarine).

Topaz is also different. I don't think the OP was asking about gemstones (since in that case the post would have specifically mentioned the gemstone names).

[Edited on 10-30-2016 by Metacelsus]

unionised - 30-10-2016 at 05:58

Quote: Originally posted by Metacelsus  
Quote: Originally posted by j_sum1  
I assume you are looking at gemstones -- essentially looking at the difference between beryl/emerald/aquamarine and rubies.


Beryl isn't beryllium oxide. It's a beryllium aluminum silicate (as are emerald and aquamarine).

Topaz is also different. I don't think the OP was asking about gemstones (since in that case the post would have specifically mentioned the gemstone names).

[Edited on 10-30-2016 by Metacelsus]

Topaz is one of the reference materials on the Moh's scale of hardness. It really doesn't matter in this context if it's made from eye of newt.

zed - 30-10-2016 at 14:44

Huh? You have to give us more information. I had a buddy that sometimes used Beryllium Oxide, in prototype electronics applications. Mixed it with grease, that he applied at Power Transistor/Heatsink junctions.

In later years, this caused me stop everything, and thoroughly wash my hands every time I encountered white grease inside an electronics devise.

Beryllium Oxide can mess you up. Skin exposure too.

https://en.wikipedia.org/wiki/Beryllium_oxide
https://en.wikipedia.org/wiki/Berylliosis

[Edited on 30-10-2016 by zed]

[Edited on 30-10-2016 by zed]

j_sum1 - 30-10-2016 at 14:48

Quote: Originally posted by Metacelsus  
Quote: Originally posted by j_sum1  
I assume you are looking at gemstones -- essentially looking at the difference between beryl/emerald/aquamarine and rubies.


Beryl isn't beryllium oxide. It's a beryllium aluminum silicate (as are emerald and aquamarine).

Topaz is also different. I don't think the OP was asking about gemstones (since in that case the post would have specifically mentioned the gemstone names).

[Edited on 10-30-2016 by Metacelsus]

Good point. Well spotted.
I reacted to the comment that it was attached to something. So this makes me wonder what the application is. I am struggling to conceive of a situation where the two could be confused.

aga - 30-10-2016 at 15:10

Quote: Originally posted by Eric Slighton  
It is in an assembly & hard to take out.

Most likely that Señor Eric is taking a microwave oven apart and is worried about the beryllium oxide used in the making of the magnetron.

It would help if the OP could be more specific about what they are doings/wantings knowings of.

[Edited on 30-10-2016 by aga]

wg48 - 30-10-2016 at 16:33

There are no significant amounts of beryllium oxide in domestic microwave oven magnetrons.

There is no reason why there would be. These days if there was the oven would probably require a health warning along with its magnetron and the sale of such ovens would be illegal in California and probably the EU as well LOL.