Eucrite
A basaltic achondrite, a frozen lava or shallow intrusive rock from the crust of the asteroid Vesta.
Eucrites are the most common achondrites and the volcanic member of the HED family. They are made chiefly of two minerals: pigeonite, a low-calcium pyroxene, and calcium-rich plagioclase feldspar. Some cooled quickly as lava flows and have fine, basalt-like textures; others, called cumulate eucrites, cooled slowly deeper in the crust and grew larger crystals.
They matter because they show that a small asteroid melted, separated and erupted lava within only a few million years of the Solar System's birth. Most eucrites were later reheated and shocked, and many are breccias. Classic examples include Juvinas, which fell in France in 1821, and Stannern, which fell in Moravia in 1808. Millbillillie, which fell in Western Australia in 1960, is popular with collectors for its glossy black crust.
A fresh eucrite usually has a shiny, jet-black fusion crust over a pale grey interior, a striking contrast that experienced hunters look for. Inside you may see white feldspar laths and dark pyroxene, or angular fragments if it is brecciated. Eucrites are weakly magnetic or not at all, because they contain very little metal. Like any find, they should be collected only with the landowner's permission and within local laws.
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