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Chemistry Forums for Students => Analytical Chemistry Forum => Topic started by: MrMoon on August 06, 2021, 01:04:16 PM

Title: How to identify Pigments?
Post by: MrMoon on August 06, 2021, 01:04:16 PM
Hi,
I need help or links to recources that can help me identify several containers of pigment powder.
(if this is the wrong part of this forum please notify me)
(Im new to this forum and my chemical supplies are very limited)

My great grandfather sadly passed away and I now own several unlabled containers of pigment powder but I don't know what kind of pigments.
I would like to know how I can identify what kind of pigments I have.
I know that some kinds of pigments are dangerous to the respiratory tract so I handled them with caution.

The pigments are stored in 8 metall cans, specifically 1 can of white, 2 shades of blue, 3 shades of red, 1 orange and 1 yellow.

I can't really find any material about this topic online and I hope to find some information here, feel free to ask for additional information if needed. I don't have acces to a lab but I can perform some simple test that can be done in a kitchen or in the backyard ;)

Thanks!
Title: Re: How to identify Pigments?
Post by: MOTOBALL on August 06, 2021, 05:33:37 PM
If the containers are totally unlabeled, you really have very little chance of doing a definitive identification. There is a publication called The Colour Index (google it) that lists pigments by their Colour Index number (CI number) and gives their chemical structures. You have 3 reds, there are probably 10-50 or more reds listed, same for the blues etc. There are no simple tests that you can do to identify them. Positive ID would require expensive analytical equipment and personnel.
Title: Re: How to identify Pigments?
Post by: MrMoon on August 07, 2021, 07:11:33 AM
Okay but still thank's allot for the answer. :) I will see what I can find out through color-index.
Title: Re: How to identify Pigments?
Post by: Corribus on August 07, 2021, 10:09:52 AM
If you were willing to spend a little bit of money you might be able to identify them with a colorimeter, which can measure L*ab color values that could be compared to literature values. If they exist. Long shot though.  It's hard to do simple tests on pigments because they are intentionally manufactured to be stable. You really need expensive analytical equipment like FTIR, ICP-MS, XRF etc. You could send the samples for professional analysis, maybe a few hundred bucks.

EDIT: if you google pigment identification you will find some other information. Another thing I thoug might of: I dont know where you live but many art museums and conservatories have labs that can do this kind of things. If you have any museums near you, you might reach out to them and see if they'd be willing to help you identify the pigments. The analysis isnt expensive once you have the equipment. Lay on the charm and they might do you a favor. If nothing else, they could help steer you in the right direction.