Warren: Sounds like you have a metal contamination or some otheralloy problem. The only thing I can think of that will make themetal crumble. I suggest you start with a new batch of silver anduse a rolling alloy until you get the hang of it and then try mixingyour used scrap 50/ 50 with fresh metal.. Give a call to one of therefining houses and tell them what you need in an alloy and see whatthey recommend. I personally use United Precious Metals S88 masteralloy for sterling, which is a low ox alloy. I use it for casting aswell as milling and have had no problems. I have however found thatit does work harden a little faster that milling stock and has to beannealed more frequently when hammer forging. Frank Goss
When preparing large stock I was taught to forge the resultingingot. Get it red hot and belt it with a hammer in all directions -like working iron. I seldom get any porosity problems.
Tony KonrathKey West Florida 33040