# found some unusual metal contacts



## azgard (Apr 24, 2011)

i was taking apart an old leeds northrup testing device. dating back to the 20s or 30s or older. there were some old potentiometer looking things with a contact point that rotated around a coil when you turned know. they are big about 1/8th inch diameter and 1/4 inch long. attached to a copper arm thing. These cylinder shaped things are Extremely hard. i could not sratch them with my steel file or knive blade. i rubbed it on a stone for my gold /platinum kit it barely left a mark. i am not sure how to use platinum test acid. anyone know if these could be platinum or another hard metal like tungsten or something. ill get some pics up later.


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