Suevite

Meteorite, tektite, or impactite

Also called Impact breccia

About it

Impact breccia of rock fragments and flattened blobs of dark impact-melt glass in a fine matrix. Named for Swabia; its type locality is the Ries crater in Bavaria, where it was used to build St. George's Church in Nördlingen.

Type
Meteorite, tektite, or impactite (impactite)
Group
Impactite (impact breccia)
Colours
grey, greenish grey, with dark glass bits
Transparency
opaque

Typical values: real specimens vary. For more, see mindat.org.