Monthly birthstones symbolize the month of birth according to the Gregorian Calendar.
The ancient Hindus called the Diamond "Vajra," meaning lightening, both because of the sparks of light thrown off by this gem as well as its invincible strength. The Diamond is harder than any other substance on earth.
The April birthstone of the Diamond is considered to be the birthstone for Aries (The sign of the Ram) and relate to those born between March 21 - April 19. The Zodiac sign of Aries also responds to Bloodstone, Topaz, Sapphire, Jasper, and Aquamarine