China stone (occasionally Cornish stone or Cornwall stone) is a medium grained, feldspar-rich partially kaolinised granite characterised by the absence of iron-bearing minerals.
Its mineral content includes quartz, feldspar and mica; accessory minerals include kaolinite and fluorspar. It is found in one area near St Austell, Cornwall in the United Kingdom. It was the last UK sourced feldspathic material to be commercially extracted.
Satin spar, less commonly atlas spar, is a trivial, partly obsolete name for fibrous varieties of the minerals gypsum, calcite, and aragonite. Satin spars have a characteristic satin (silky) luster. Despite their very low hardness (2 or 3 on the Mohs scale), satin spars are widely used as ornamental stones.
Spar is a general term for glassy, transparent to translucent minerals that cleave easily. Satin spars are not related to other minerals containing spar in their names, such as feldspar and fluorspar.