Speculum metal is a mixture of around two-thirds copper and one-third tin making a white brittle alloy that can be polished to make a highly reflective surface. It is used primarily to make different kinds of mirrors including early reflecting telescope optical mirrors. Speculum metal can also be used as the metallic coating on glass mirrors (as opposed to silver or aluminium) giving a reflectivity of 68% at 6000 angstroms when evaporated onto the surface.
Read more about Speculum Metal: Overview, Speculum and Telescopes
Famous quotes containing the words speculum and/or metal:
“God bless the physician who warms the speculum or holds your hand and looks into your eyes. Perhaps one subtext of the health care debate is a yen to be treated like a whole person, not just an eye, an ear, a nose or a throat. A yen to be human again, on the part of patient and doctor alike.”
—Anna Quindlen (b. 1952)
“There is a lot of talk now about metal detectors and gun control. Both are good things. But they are no more a solution than forks and spoons are a solution to world hunger.”
—Anna Quindlen (b. 1953)