Clay is made up of clay minerals, and clay minerals are chemically weathered from minerals such mica and felspar.

B. Velde has written:

'The origin of clay minerals in soils and weathered rocks'

'Archaeological ceramic materials' -- subject(s): Pottery, Archaeological chemistry, Petroglyphs, Analysis

'Introduction to clay minerals' -- subject(s): Clay minerals, Analysis, Clay

'Clay minerals' -- subject(s): Clay minerals

Clay minerals are sheet silicates.

Water and air are not minerals; granite, porphyry, clay, pumice are rocks, not minerals.

No clay is not an organic material, it is made from minerals.