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 Replies: 6 / Views: 1,201 |
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Valued Member
United Kingdom
287 Posts |
After taking coins out from a soak, I heated some in the oven to dry them out, I put them in for about 15 - 20 mins, @ about 170.
Left um on the side and went back to them in the morning. This particular coin (which had good detail!) All of the patina was flaked, I knew it was ruined, but I thought id give it a gentle dry brush to see what would happen, and literally all of the detail just brushed off, literally now the coin is nothing but flat metal.
Did I put it in oven for too long? not long enough?
Any thoughts appreciated
Thanks
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Pillar of the Community
United States
3486 Posts |
I'd say too high a temperature.
If this method is used a constant monitoring is needed.
Try an electric hair dryer next time. Better control of how much heat.
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Pillar of the Community
United States
4981 Posts |
that's about where I run and how long. did I type of dusty blue stuff form by any chance?
i only dry my coins when I'm done cleaning, so I only do it one time. are you doing this every time you have a cleaning session? maybe repeated heating and cooling is bad? in the summer, i'll stick them in a pie tin and leave them in direct sunlight..that works good...seasonally.
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Moderator
 United States
23731 Posts |
Can you take a picture of the coin. The problems with heating ancient coins is that after all the centuries of being buried in the ground the metal has become porous and in some cases calcified. When you heated the coin and left it out to cool, it drew in all the moisture from the surrounding air. If you are going to heat your coins, your gong to need a bell jar, some rubber and a cooling try so the rubber doesn't melt. Place the rubber on a level surface the cooling try on it and the bell jar over it. The rubber seal the jar so no moisture gets in and the coin should not chance. Too much heat will also hurt the coin like Mattewvincent said.
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Pillar of the Community
United States
2480 Posts |
Once, while experimenting with cleaning some slugs, I heated one with a torch. Got it a little too hot... little blobs of shiny lead bubbled out like popping a metallic pimple. I didn't try that again. It was kinda cool though :D
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Valued Member
 United Kingdom
287 Posts |
It was the first time heated it.
I had a batch of coins, that I was making decisions on. I had a few that I'm satisfied with results so was drying out to ID, and others that I wasn't sure weather to class as a cull. so it was the first time of heating.
It was dusty, but more green that blue, if your curious of BD, I wouldn't have said it had BD.
I think the safest way would be hair dryer then? If I am satisfied with a coin, it will go in a flip going forward straight away after dried to avoid damage again. Although I am at learning/experimenting stage, I don't want to sacrifice history due to experimenting if that makes sense.
Cheers guys
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Bedrock of the Community
Australia
21788 Posts |
Sun drying is best, if not let them dry naturally in a warm dry location in your house.
Too much heat will ruin them, especially ancients with a thick patina. Been there, done that. Never again!
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Replies: 6 / Views: 1,201 |
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Posted 03/14/2014 4:48 pm
