This meteorite is part of a large one, known as Toluca, which fell in ancient times in Xiquipilco, Mexico State, Mexico. Known as an "individual", it is a complete chunk that broke off the main piece as it was falling to earth. This particular chunk was at one point in the collection of Oscar Monnig, and was given his catalog number M8.137. I don't know when this chunk was found, but samples first started making their way out of Mexico in the late 1700's.
This is one of the most expensive samples in my collection, but it's also one of the most fascinating. It's a real live space rock, a chunk of a failed planet that you can hold in your hand. How can you put a price on that? (Easy: eBay can put a price on anything.)
The outside surface is smooth, presumably from melting during fall. If this piece were cut in half (heaven forbid!), the inside would probably look a lot like the sample below.
I chose this sample to represent its element in my Photographic Periodic Table Poster. The sample photograph includes text exactly as it appears in the poster, which you are encouraged to buy a copy of.
Source: eBay seller meteoritesandmore
Contributor: Theodore Gray
Acquired: 10 October, 2005
Text Updated: 11 August, 2007