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How to use color filters for testing gems


How do you use a red ruby filter to test for different stones? Thanks.


Well first of all, ruby as well as Chelsea filter are basically the same item marketed under a different trade name.

You can really use such a color filter for many different tests of different gems, not just Rubies. There are ‘potential resulting lists’ of what you should see with/without such a filter floating around, just search Google. However I would recommend not to take such a result as a primary mean, you should always confirm through other means


Im curious on your take on hanneman filters.

Do you need them to identify tanzanite?

And how about sapphires?

Under my chelsea filter I have 2 sapphires that appear green.

And the tanzanite under the same filter is a gold/brown.

Im basically asking if I should buy the tanzanite filter along with the ruby/aqua set.

Any input is appreciated.