Pitchpipe

PITCH'PIPE, n. An instrument used by choristers in regulating the pitch or elevation of the key or leading note of a tune.

PITCH'-STONE, n. A mineral, a sub-species of quartz, which in luster and texture resembles pitch, whence its name. It is sometimes called resinite. Its colors are, several shades of green; black with green, brown or gray; brown, tinged with red, green or yellow; sometimes yellowish or blue. It occurs in large beds and sometimes forms whole mountains.