To convert a signed binary int to a decimal number, use the following algorithm. We illustrate the algorithm on two four-bit examples: 1110 and 0101. If the leftmost bit is a 1, the number is negative. Do the following... (1110 starts with a 1.
Copper pyrites is a common name for the mineral chalcopyrite, which has a formula CuFeS2. It can be considered to be made up of Cu+ Fe3+ S2- ions but there is covalent character.
Orthoclase, or orthoclase feldspar (endmember formula KAlSi3O8), is an important tectosilicate mineral which forms igneous rock. The name is from the Ancient Greek for straight fracture, because its two cleavage planes are at right angles to each other. It is a type of potassium feldspar, also known as K-feldspar. The gem known as moonstone (see below) is largely composed of orthoclase.