How can you tell if it's carbide?

[Rotate]

I have a box full of small drill bits used for drilling holes in printer circuit boards. Is there any of determining which are HSS and which are solid carbide. I know that HSS dulls fairly quickly when drilling PCB, but I'd rather not dull them to find out.

Albert

[gvasale]

find another drill you know to be of hss or carbon steel. the carbide is heavier. also carbide does not have as much magnetic attraction s steel.

[Thrud]

Albert
If you are talking about the ones PA and Lee Valley sell they are solid carbide and fragile. Make sure your work is held ridgidly as movement can snap them like glass. The ones under 1/8" can go to 60,000+ rpm.