These are fragments from a meteorite that hit the moon and then caused moon rock to land on earth.  The cases are 2.25" long, 1.5" wide, and 0.5" thick. They weigh approximately 8 grams.

Its card reads:

MOON ROCK
A piece of lunar meteorite
NWA 4734

It is illegal for private citizens to buy, sell, or possess moon rocks or dust brought back from the Apollo missions. These rocks were NOT brought back by Apollo and are perfectly legal to buy, sell, and possess.

Product of Earth's Moon, Discovered in Morocco, Packaged in the USA