41. These sediments preserved the aragonite of the shells, preventing it from converting to calcite. 42. Shells are almost always composed of polymorphs of calcium carbonate-either calcite or aragonite . 43. Aragonite will change to calcite at 380 470 �C, and vaterite is even less stable.44. Major commodities which are dependent on the port include citrus exports, cement and aragonite imports. 45. The shells are formed of aragonite , although the cameral deposits may consist of primary calcite. 46. Cuttlebone is composed primarily of aragonite . 47. The interior is covered with dazzling white crystals composed of gypsum, calcite, and aragonite . 48. The shells are usually preserved as calcium carbonate usually any aragonite is pseudomorphed with calcite. 49. We are actually living in aragonite sea period currently, so my answer now seems inconsistent. 50. The resultant white carbonate ( aragonite ) is the same mineral that makes up natural coral reefs.
