Message:

<p>[QUOTE=&quot;desertgem, post: 1645603, member: 15199&quot;]A few months in olive oil ( change occasionally) shouldn&#039;t hurt at all as the patina is over the metal, and there may be small cracks which would allow oil to get under the edges. Since it is an experiment, after a few weeks try some thermal cracking by moving it into a freezer for a few hours and then quickly into <b>warm </b>oil ( such as&nbsp; warmed massage oil temperature, not deep frying <img src="styles/default/xenforo/clear.png" class="mceSmilieSprite mceSmilie1" alt=":)" unselectable="on" unselectable="on" />)&nbsp; Since the metal and the overlying patina have different expansion coefficients, it might help. </p><p><br /></p><p>I like desert patina on ancient coins, and think it is a preservative as once the metal is covered by a thin layer, the surface of the coin is protected from atmospheric reactants.&nbsp; Here are 2 references, one easy read and one much harder.</p><p>I became interested in silicates due to &quot;Water glass&quot; used in lapidary work and&nbsp; pottery glazes for a previous hobby.</p><p><br /></p><p>general reading :&nbsp; <a href="http://www.asdn.net/asdn/chemistry/silicates.shtml" target="_blank" class="externalLink ProxyLink" data-proxy-href="http://www.asdn.net/asdn/chemistry/silicates.shtml" rel="nofollow">http://www.asdn.net/asdn/chemistry/silicates.shtml</a></p><p><br /></p><p>much harder ( .pdf): <a href="http://www.ceramics-silikaty.cz/2005/pdf/2005_04_287.pdf" target="_blank" class="externalLink ProxyLink" data-proxy-href="http://www.ceramics-silikaty.cz/2005/pdf/2005_04_287.pdf" rel="nofollow">http://www.ceramics-silikaty.cz/2005/pdf/2005_04_287.pdf</a>[/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