Ilmenite is an iron titanium oxide, it is the principal ore of titanium. It is black (or dark gray) and has a metallic luster. It is usually weakly magnetic. The mineral itself is actually not magnetic but it is often intergrown with magnetite, which very strongly responds to the magnetic force. You can use a hand-held magnet to test sand grains. If they are only lazily turning themselves but not jumping vigorously towards the magnet, then they are most likely ilmenite grains, not magnetite.
Uses of Ilmenite:
Ilmenite is the primary ore of titanium metal. Small amounts of titanium combined with certain metals will produce durable, high-strength, lightweight alloys. These alloys are used to manufacture a wide variety high-performance parts and tools. Examples include: aircraft parts, artificial joints for humans, and sporting equipment such as bicycle frames. About 5% of the ilmenite mined is used to produce titanium metal. Some ilmenite is also used to produce synthetic rutile, a form of titanium dioxide used to produce white, highly reflective pigments.
Most of the remaining ilmenite is used to make titanium dioxide, an inert, white, highly reflective material. The most important use of titanium dioxide is as a whiting. Whiting are white, highly reflective materials that are ground to a powder and used as pigments. These pigments produce a white color and brightness in paint, paper, adhesives, plastics, toothpaste, and even food.
Titanium dioxide is also used to make powders with a tightly controlled particle size range. These powders are used as inexpensive polishing abrasives in a variety of lapidary work that includes rock tumbling, lapping, cabbing, sphere making, and faceting. Titanium oxide abrasives are used in many other industries.