March's Birthstone is Aquamarine

The name aquamarine was derived by the Romans, "aqua" meaning water and "mare" meaning sea, because it looked like sea water. They were considered sacred to Neptune, god of the sea. This association with and safe voyages as well as protection against perils and monsters of the sea. Its first documented use was by the Greeks between 480-300 BC. They wore aquamarine amulets engraved with the god Poseidon on a chariot.
Beginning in the Roman period.

The aquamarine was believed to possess medicinal and healing powers, curing ailments of the stomach, liver, jaws and throat. During the Middle Ages, it was believed to be an effective antidote against poison. Aquamarines were thought to be the source of power for soothsayers, who called it the "magic mirror", and used it for telling fortunes and answering questions about the future. It is said that Emperor Nero used it as an eyeglass 2,000 years ago, and much later, aquamarines were used as glasses in Germany to correct shortsightedness. In fact, the German name for eyeglasses today is "brille", derived from the mineral beryl.

Aquamarines vary in color from deep blue to blue-green of different intensities, caused by traces of iron. Naturally occurring deep blue stones are the most prized because they are rare and expensive. However, yellow beryl stones can be heated to change them to blue aquamarines.

Bloodstone is the second birthstone for March .

Bloodstone. It's a favored material for carving religious subjects, particularly the crucifixion. One particularly famous carving was done by the Italian Matteo del Nassaro around 1525. In "The Descent from the Cross", the carving was carefully crafted so that spots of red on the bloodstone represented the wounds of Christ and His drops of blood. According to legend, bloodstone was believed to have formed during the crucifixion of Christ. A Roman soldier-guard thrust his spear into Christ's side and drops of blood fell on some pieces of dark green jasper lying at the foot of the cross, and the bloodstone was created.

Bloodstone is a form of the abundant mineral quartz. This particular form of quartz, known as cryptocrystaline quartz, exists as a mass of tiny quartz crystals formed together in large lumps that show no external crystal form, yet each of the component crystals that make up the mass is a genuine crystal. This quartz variety is also called chalcedony. Green chalcedony, spotted with flecks of red is known as bloodstone. Bloodstone can be found embedded in rocks, or as pebbles in riverbeds. The best sources of this stone are India, Brazil and Australia.

Babylonians used this stone to make seals and amulets, and it was also a favorite with Roman gladiators. In the Middle ages, bloodstone was believed to hold healing powers, particularly for stopping nosebleeds. Powdered and mixed with honey and white of egg, it was believed to cure tumors and stop all types of hemorrhage. Ancient alchemists used it to treat blood disorders, including blood poisoning and stopping the flow of blood from a wound. Bloodstone was also believed to draw out the poison of snakes.