• Register

Information for users from the old Q&A site
If you have an account from our old Q&A site, your account was transferred over, but you need to reset your password and confirm your email address.
Reset Password here
Confirm Email here

2,161 questions

3,789 answers


26,756 users

Difference between 2 specific minerals

0 votes

What is the difference between common opal and chalcedony?

asked Jun 3, 2014 by Outback Bob (120 points)

1 Answer

0 votes

Opal contains water in its chemical structure and is amorphous, whereas chalcedony does not contain any water and is microcrystalline. Opal's hardness is about 5.5 whereas chalcedony is 7. Hope this information is helpful.

answered Jun 6, 2014 by hershel (51,840 points)