I recently ordered this box of 26 awg colored wires from Amazon.
The add says that it is copper in two places.
In the main add it lists several things, one of which is Material: Tinning Copper (Which I assume to man tinned copper).
Also, down at the very bottom of the page where more there are more details, the material is also stated as copper.
Wen I strip this wire, it is silver, and that is OK, if it is tinned.
However, when I scrape it, I get no copper.