Crystals can remain unchanged for millions of years because their constituent atoms are arranged in a stable, regular pattern, called a lattice. This lattice repeats throughout the crystal and ensures that every crystal of the same mineral will show the same geometrical characteristics, with the same number of flat faces always meeting at the same angles. This precise repetition is the same no matter what size the crystal or whether it is a faceted gem or a dull, rough piece. A crystal’s external form is simply a reflection of its internal atomic structure. These shapes have a significant influence over the magickal and healing properties of a crystal.
The lattices fall into seven major types. Different minerals that share the same core pattern will have similar basic shapes. Unfortunately, these simple forms are seldom obvious from the external appearance of crystals owing to the variable conditions in which they form. However, careful scrutiny will allow you to recognize certain identifying traits (for example, the hexagonal cross-section of quartz or emerald).
The link between heavenly bodies and gems is continued in the concept of birthstones. Birthstone lists vary because some are arranged according to the zodiac and some according to calendar months. The list presented here is an abbreviated list of the most authentic traditions. However, it is always more beneficial to use a stone to which you are attracted too, rather than one you feel you should have simply because it is linked to your zodiac sun sign, which is only one aspect of your full birthchart.
Aries (Mar. 21 – Apr. 19) – carnelian, bloodstone, jasper, diamond
Taurus (Apr. 20 – May 20) – tourmaline, tiger’s eye, topaz, emerald.
Gemini ( May 21 – Jun. 20) – aquamarine, citrine, chrysocolla, tiger’s eye, pearl
Cancer (Jun. 21 – Jul. 22) – moonstone, pearl, ruby, emerald
Leo (Jul. 23 – Aug 22) – ruby, heliodor, sunstone, clear quartz
Virgo (Aug. 23 – Sep. 22) – sapphire, peridot, carnelian, citrine
Libra (Sep. 23 – Oct. 22) – lapis lazuli, opal, aventurine, peridot
Scorpio (Oct. 23 – Nov. 21) – obsidian, Herkimer diamond, topaz, aquamarine
Sagittarius (Nov. 22 – Dec. 21) – blue quartz, amethyst, malachite, turquoise
Capricorn (Dec. 22 – Jan. 19) – jet, black onyx cl,ear quartz, black tourmaline
Aquarius (Jan. 20 – Feb. 18) – amethyst, sapphire, chalcedony, garnet
Pisces (Feb. 19 – Mar. 20) – turquoise, pearl, rose quartz, aquamarine