Rosetta Stone is dark granodiorite, not basalt

Rosetta Stone isn't black basalt.

The Rosetta Stone is granodiorite from near Aswan, Egypt.

The stone carries a decree issued in 196 BC during Ptolemaic Egypt.

Inscriptions were chalked white and covered with wax to protect them.

Cleaning in 1999 removed coatings and showed dark grey and pink veins.

The stone is 112.3 cm high, 75.7 cm wide, 28.4 cm thick.

Weight of the stone is about 760 kilograms or 1,680 pounds.

Three scripts appear: Egyptian hieroglyphs, Demotic, and Ancient Greek.

French officer Pierre-François Bouchard found the stone in 1799.

Decoding the stone helped scholars understand Egyptian hieroglyphs.

The decree honors King Ptolemy V with gifts and temple celebrations.

The stone likely came from a temple at Sais, Egypt’s ancient city.

British forces took the stone to London in 1801 after French defeat.

Studies began in 1803; Champollion deciphered hieroglyphs in 1822.

The Rosetta Stone is often mistaken for black basalt stone.