Is Snowflake Obsidian Safe In My Fishtank

[bristlenoseitplecoman]

I know normal obsidian is safe but im not sure if snowflake obsidian is also safe.

 

[Crossfire]

I know normal obsidian is safe but im not sure if snowflake obsidian is also safe.

Drop some vinegar on the rock. If it fizzes, then it's unsafe. Another way to do it, is put the rock in a bucket of water. Check the pH before adding the rock. A few days later, check the pH of the bucket water. If it's higher or lower, then it's unsafe.

A good scrubbing and soaking before adding (should it be safe) should also ensure saftey

 

[Essjay]

As you already know, obsidian is a volcanic glass and unreactive. The white inclusions of snowflake obsidian are cristobalite, which is a form of quartz (SiO[sub]2[/sub], the same as sand). I think it should be OK in a fishtank.

Information from http/www.mindat.org/mineralindex.php