I know a 30 watt can cut, albeit slowly. Interested in cutting .7mm sterling silver. I've been told that it's possible but I'm skeptical. I've been told that 20 watt was the minimum, and that 10 watt is impossible. I know someone with a 50 watt and she said it's like slicing through butter with her 50 watt. What say all of you guinea pigs, errrrr I mean, fiber laser engravers.