What household objects are made of metals with a high degree of purity?

I've looked into this briefly and from what I've understood, the kind of copper that's used to make electric copper wire is generally of a high purity (well above 99%). What are some other household objects that may be primarily composed of highly pure/unalloyed metals?




As you mention, [electrolytic copper](https://en.wikipedia.org/wiki/Copper_conductor), used in electronics, is >99.9% Cu.


Household aluminum foil is [~99.8% Al](http://www.madehow.com/Volume-1/Aluminum-Foil.html), though it migh be alloyed for greater strength.


You *might* find fairly pure [lead used for plumbing or ammunition](https://www.shootersforum.com/threads/pure-lead-test.80473/), but it is often alloyed to make it harder. A *very* rough [purity test can be performed with different grade hardness pencils](https://www.northwestfirearms.com/threads/how-to-tell-if-its-lead-or-a-lead-alloy.251851/).


Fairly pure tin is used for specialty solder, e.g., for items that come into food contact. Ordinary solders were Sn/Pb alloys, where lead has been replaced with Bi or other lower melting point metal now.


Mercury of [~99.9% purity](http://www.madehow.com/Volume-4/Mercury.html) might be found in old thermometers and "silent" electric switches.


Tungsten wire in lamp and valve (radio tube) filaments was fairly pure, but is now "doped" with oxides, including thorium, to make it stiffer and increase electron emission.


One might have a titanium tooth implant, or tantalum joint implant, but I don't know the purity of those materials.


Jewelry made of *pure* Au, Ag or other such metal is rare, since they would lose shape quickly, even take fingerprint impressions. Perhaps precolumbian New World artifacts? Stronger Pt might be used, but is difficult to find >90% pure. One might find a tiny amount of pure Au in gold lettering, or in the radiation emitter in a smoke alarm. Yes, a radio-emitter is added to the gold foil, but <<0.1%.


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