Calico basic unfinished is not washed, softened or treated. It is straight from the loom, it will have flecks and it will shrink considerably. It will whiten and soften with washing. Buy by the roll or per metre.
Calico means different things to different people. It was named after Calicut (not Calcutta) which is on the west coast of India and used to be a big trading centre for cotton. Vasco de Gama, a Portugese explorer 'discovered' Calicut in 1648, and so began the exploitattion of India which continues to this day.