Multiple choice general knowledge Tourmaline,Carnelian,Lace agate, Malachite are types of Cars Cloth Adhesive Gemstones Reveal answer Fill a bubble to check yourself D Correct answer Explanation These are all semiprecious stones or minerals used in jewelry and ornamental objects. Tourmaline and malachite are mineral crystals, carnelian is a variety of chalcedony, and lace agate is a banded form of agate.