# What is the chemistry behind black colour of platinum black? [duplicate]

Platinum is a silvery white metal and is highly unreactive then why it's powdered form "platinum black" is platinum metal but is black in colour. why would a metal such as platinum become black as a powder?

• Might be related to light scattering from small particles of platinum (platinum black is a fine powder) vs. bulk, but not sure. Good question! – Todd Minehardt Feb 11 '16 at 17:19
• @ToddMinehardt is right, it's not about the chemistry, it's about the physics of how light interacts with it. As good as a question as it is, I'm flagging it as off-topic for Chem.SE, as it more properly belongs on Physics.SE. – hBy2Py Feb 11 '16 at 17:27
• @ToddMinehardt For reference, this answer on Physics.SE has a short paragraph about a related modification of $\ce{Pt}$ that also leads to a black color. – hBy2Py Feb 11 '16 at 17:41
• I wrote a relevant answer in a past question. – Nicolau Saker Neto Feb 12 '16 at 8:38
• While the answer might be that's it's a physical effect rather than a chemical one, the question is still about a particular compound and the user wouldn't have known that it was a physical effect or else they wouldn't have asked here, so I'm glad the hold was removed. – Tyberius Mar 27 '19 at 14:05