Diamond Dust Mirror

June 12, 2006 8:39 PM

What can you tell me about diamond dust mirrors and how they were made?

Apparently "diamond dust" mirrors were fairly popular around the turn of the 20th century, but I can't seem to find any good info on them. I've got one search result that defines "diamond dust" as an effect that's caused by the mercury backing on the mirror degrading, but no other sites seem to agree with this. I've found tons of results talking about, describing, or even with pictures of diamond dust mirrors, but none have much information as to what actually qualifies a mirror to be called a diamond dust mirror, whether actual diamond dust is really used to make them, and if so, how.

And if you really want to know, this is for a historical reenactment event - a guided tour of an old mining town. I'm playing a local saloonkeeper, and reports say his saloon featured a large diamond dust mirror behind the bar. In fact, one of the more colorful stories about the saloon and its patrons involves the mirror, and the source of this tale stresses that it was a diamond dust mirror, but doesn't explain what that means.

posted by attercoppe to grab bag (4 comments total)

Diamond dust is used as a very mild abrasive and may have been used to polish mirrors to very high reflectivity. It appears to be used today for mirrors used in astronomy.
posted by Mr. Six at 8:48 PM on June 12, 2006

Modern mirror-making (i.e. with float glass) didn't occur until the 1900's. Mirrors were routinely made with tin and mercury before then, because it was difficult to get truly flat sheets of glass.

Modern use of diamond dust in manufacturing is due to the fact that industrial diamonds can now be produced fairly cheaply.

I would guess that "diamond dust" doesn't have anything to do with the manufacturing process, only the appearance of an antique mirror with fine cracking and perhaps the desire of antique salespeople not to point out that the mirrors contain mercury in possibly harmful amounts.
posted by jellicle at 5:33 AM on June 13, 2006

"That phenomena that sometimes occurs when mercury backed mirrors begin to break down appearing as if diamond dust were blown on the mirror."

http://www.mirrorx2.com/Non_frames/terms.html
posted by jdfan at 1:16 PM on June 13, 2006

jdfan, that's the one site I referred to that no one else seems to agree with.
posted by attercoppe at 5:23 PM on June 13, 2006