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Nine Carat "Gold"

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We bought ourselves new wedding rings this week. We were married with titanium ones - a very geeky choice, very typical of us, but they've not been great.

For a start they mark glass and ceramics, so you have to take them off before doing the washing up and be very careful if wiping the car windscreen not to let the ring touch it as it's a pain to remove.

In addition neither of our rings fitted that well and you can't adjust them, unlike gold. I've got used to it but Beth actually lost hers while we were out hunting rabbits when it simply slipped off and she didn't notice so she's been wearing a gold ring I bought her earlier in its place.

So anyway, after much debate over various designs, we ended up buying ourselves two plain band nine carat gold rings.

Now I've always know that nine carat gold is only 9/24ths gold (37.5%) - that's the definition of a carat: it's a 24th.

But what's the rest of it? I've always blithely said "brass" when asked. Well it turns out I was half right, it is generally around 50% copper but the other half isn't zinc but silver. So nine carat "gold" is really only 37.5% gold plus, typically, 31.25% each of copper and silver.

Written 18/07/08

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A Quite Impossible Proposal: How Not to Build a Railway by Andrew Drummond The Wilt Alternative by Tom Sharpe

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