Message:

<p>[QUOTE=&quot;desertgem, post: 8251263, member: 15199&quot;]Your question about the grayish color inside the loop of the B, it likely is copper oxide. There is 2.5% copper mixed with the zinc and heat from the grinding matrix can oxidize both metals, zinc is a white oxide while copper oxide is deep black . My thought is that the part in the photo above , the letters rising higher than the surface would have more heat generated by the longer exposure to the grinding and the much darker copper oxide buildup whereas the inside is mixed but less heat and thus grayish. Theory, just theory/&nbsp; Jim[/QUOTE]</p><p><br /></p>

Your name or email address:

Do you already have an account?

• No, create an account now.
• Yes, my password is:
• Forgot your password?

Stay logged in