For 10 points, name this class of aluminum silicate minerals, which make up about 60% of the earth's crust.
One type of this substance corresponds to the continuous, or rightmost, branch of Bowen's reaction series; another type is polymorphous with microcline and sanidine. Three types of this non-quartz material are used in the QAPF diagram to classify other substances. One variety has [*] sodium or calcium in its chemical formula, while another contains potassium and is a 6 on the Mohs scale; those varieties are plagioclase and orthoclase. For 10 points, name this class of aluminum silicate minerals, which make up about 60% of the earth's crust.
One type of this substance corresponds to the continuous, or rightmost, branch of Bowen's reaction series; another type is polymorphous with microcline and sanidine.
{feldspar} [accept {plagioclase feldspar} until “{another type}” is read]