if i have a metal does anyone know a cheap easy test to see if its platinum or not and its purity :?:
any help would be much appreciaded

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I already know I'm going to get blasted for this, since it's my answer for everything. Dip it in some nitric acid, since the metal is used as an electrode quite frequently I would dobut the nitric acid would do anything to it. If it wasn't platinum, you shoule be able to tell from the bubbling and the strange new colors. This is just an educated guess, but I think it could work.


So you have this random lump of metal and u wanna know if it is platinum. what makes you think it could be Pt? or are you just hoping it is!! sounds very conspicuous. what have you already tried I am intrigued!


While its true that Pt won't be attacked by HNO3, there are quite a few metals and alloys that aren't attacked by HNO3 as well.

It seems easier simply to weigh the thing and then plop it into a half filled graduate cylinder to determine its volume. From that you should should be able to determine its density or specific gravity; that of Pt should be fairly high and rather characteristic.

True Pt should be a silvery grey metal, soft and dense.

Further to martin17, google thinks that (after asking it +"test for platinum") the density of platinum is 21.45g/cc.


Google thinks a more extensive test (below) can be found at http// -

Begin the test for Platinum (Pt) by placing 20 drops of Aqua Regia solution onto a clean porcelain evaporating dish and boil this over a lamp flame until it is dry, then allow this to remain over the lamp flame for about an extended one second.

Place the dish where it can cool for a few minutes so as not to break the dish. After cooling, place 4cc of distilled water, (or water free from Chlorine), and reheat just to the boiling point. Filter this solution onto another clean porcelain evaporating dish. Add to this dish, Potassium Iodide equal to one grain of rice. Warm this solution slightly over the lamp flame and observe the color that appears. The results for this test will show if Platinum (Pt) is present as the solution will begin to turn to a light or dark rose color within a few minutes time.

Google thinks it's pretty smart sometimes... but doesn't know everything.


The poor-man's method would be to determine its density, since there are only 3 other elements with a density above 21.

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