Volcanic rock While still dominated by silicates, more primitive volcanic rocks have mineral assemblages with less silica, such as olivine and the pyroxenes. Bowen's reaction series correctly predicts the order of formation of the most common minerals in volcanic rocks. Occasionally, a magma may pick up crystals that crystallized from another magma; these crystals are called xenocrysts. Diamonds found in kimberlites are rare but well-known xenocrysts; the kimberlites do not create the diamonds, but pick them up and transport them to the surface of the Earth. Volcanic rocks are named according to both their chemical composition and texture. Basalt is a very
GemStone IV GemStone IV GemStone IV is a multiplayer text-based online role-playing video game (often known as a MUD) produced by Simutronics. Players control characters in a High Fantasy game world named "Elanthia". The first playable version of the game was known as "GemStone ][" and was launched in April 1988 on GEnie. It was one of the first MMORPGs and is one of the longest running online games still active. Access to the game is subscription-based (monthly fee) through its website, with three additional subscriptions levels available, "Premium," "Platinum," and "Shattered", in addition to a free-to-play model introduced in early March,