31. The fourth polymorph of Cu 2 ( OH ) 3 Cl family is clinoatacamite. 32. Andalusite is trimorphic with kyanite and sillimanite, being the lower pressure mid temperature polymorph . 33. Calcium carbonate occurs in two common polymorphs ( crystalline forms ) : aragonite and calcite. 34. The most familiar polymorph ( see figure ) comprises molecules of P 4 O 10. 35. Nickel ( II ) hydroxide has two well-characterized polymorphs , ? and ?. 36. This was the first time that Ringwood's predicted polymorph was found in nature. 37. Shells are almost always composed of polymorphs of calcium carbonate-either calcite or aragonite. 38. Four polymorphs of Piracetam exist that involve hydrogen bonding of the carbonyl and primary amide. 39. It is a member of the spinel group and a high pressure polymorph of chromite. 40. Inhibition of calcium carbonate scale deposition and crystal studies of its polymorphs have been conducted.
