Chessboard albite on plagioclase

Chessboard albite on plagioclase

The eponymous chessboard, or gridiron, texture of the albite shown here is caused by twinning (following albite law) as caused by strain. The exact origin of this texture is not well-constrained and it has been proposed as being the result of metasomatic replacement of K-feldspar or, less commonly, plagioclase or of being a primary texture.

See Callegari and De Pieri (1967) for a good summary.

Callegari, E., & De Pieri, R. (1967). Crystallographical observations on some chess-board albites. Schweiz. Mineral. Petrog. Mitt, 47, 99-110.