I am a jewler and goldsmith. I have had an ultrasonic cleaner for years, and use it for about everything that needs cleaning.

Make sure you get one with a heated tank and a timer.

I have never seen it leave a mark on soft metals like silver or gold.

I use a tablespoon of Simple Green in a quart of hot water. That will clean and degrease a field stripped 1911A1 in 15 minutes.

I put a pan full of cleaned parts into the oven at 135F for 30 minutes, then lube it and reassemble.

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