It’s been a while since I posted a stamp — this one is unusual in that it contains actual meteorite material!
In 2006, Austria Post issued a stamp with an other-worldly rock; this stamp contained 0.03 grams of meteorite dust. The dust came from a 19 kilogram stony meteorite found in Morocco in 2004. The meteorite is composed of olivine, a mineral chemically defined as magnesium iron silicate. The gemstone known as peridot is an example of gem-quality olivine.
The meteorite was crushed into a very fine dust, which was then hand-affixed to the stamp using a special adhesive. The stamp issue, called Mail From a Different World, sold for 3.75 EU (about $5.80 US, today).