The main impact point is found : a small hole 15 m in diameter identified as the Brenham crater. The collecting area is nicknamed the Kansas Meteorite Farm. According to the current estimate, 7000 kg of extraterrestrial matter reached the ground at Brenham. The fall is recent: less than 1000 years.
For over a century geologists study Brenham. A monolithic mass of 450 kg is found in 1947. Prospecting techniques are improving : the largest piece of meteorite from Brenham, weighing 650 kg, was discovered in 2005. It is estimated £ 500K for sale by Christie's in London on 20 April, lot 74.
This sample measuring 965 x 661 x 584 mm is of great scientific interest: it is a rare oriented meteorite, meaning that its drop axis is perfectly visible. It has of course been modified by its heating in the friction with the atmosphere and takes around its axis the rounded shape of an ideal thermal shield.
Composed of iron-nickel, the Brenham meteorite is also hiding olivine inclusions which are revealed by polishing. Common on Earth, olivine is a high density silicate of iron and magnesium which has also been found on the Moon and on Mars and is frequently observed in space by spectroscopy. This yellowish gemstone can be used in jewelry under the name of peridot.