Each gemstone has its own energy, which stimulates the body through the chakra system, in accordance with the individual horoscope. You should not attempt to use the energy of gems for healing without seeking the guidance of a skilled astrologer.

This is the third part of our article by leading astrologer Uma Shankar Shukla. It continues our examination of the character of some of the main semi-precious gemstones:

Peridot

Peridot, the gem with a citrus green colour, belongs to the Olivine group of silicates from forsterite to fayalite. The peridot forms prismatic crystals often in the form of grains or masses with colours that vary from bright green to those tinged with brown. It may have a yellowish streak and vitreous lustre.

Peridots are found in the islands of Zabarjad in the Red Sea, Burma, Hawaii (this variety may contain some chromium), Arizona, the Eiffel region of former West Germany, and Brazil. These gems occur in igneous rocks like basalt and gabbro, or as a metamorphic product of sedimentary rocks containing silica or magnesium, such as impure dolomites. They may even occur as crystals in meteoritic iron.

The Peridot is worn as the natural birthstone of people born in the month of august and in particular natives of the star sign of Leo. This stone is at times worn as a substitute for emerald, but usually it is worn to bring about strength of character, avoidance of too spirited a nature, a sense of discipline and rewards in military service. This stone can be worn on the ring finger of the right hand in any metal with a minimum weight of 5 carats.

Catseye

Catseyes are end members of the actinolite tremolite isomorphous series. They occur as tremolites and are known as Catseyes when they form green fibrous crystals. The same mineral in pale shades and shades of white forms nephrite jade, or if found in pink, hexagonite. The Catseyes can also be found in shades of brown or yellow. They are known as Catseyes because the polished version of the stone bears a single vertical streak, resembling the eye of a cat. Due to this unusual phenomenon, the cat's eye effect is the name given to the ability of a stone to allow a single band of light to traverse through it, known as chatoyancy. Catseyes are mined in Italy, Switzerland, Ontario, California and Arizona.

The birthstone for those born in the month of April, Catseye is associated with power in the face of adversity and the ability -- like a cat -- to cultivate the instinct of self-preservation during adversity. Catseye is prescribed in gemology as the stone for those suffering from the harmful effects of ketu or the dark phase of the Moon. The dasha (astrological period) of ketu, the Moon's south node, could last up to one and a half years, so it is advisable to consult your astrological chart before wearing the stone. Wearing a Catseye during this period can prevent negative influences on your personal life, good name and reputation, bringing gain from your work and occupation. The Catseye should be worn on the middle finger of either hand, in a ring of gold with the striation (or line) absolutely clear.

Tourmaline

One of the most interesting semi-precious stones, Tourmaline captivates the imagination of the wearer due to its multi-coloured hues. These almost give it a navratna (sacred gem) quality. This gem is worn as the bringer of wealth and in particular as a good luck charm. Rather than being worn on the person, for maximum benefit it should be kept in cashboxes, factories, stores and all places where goods, money or merchandise is kept. Once again a silicate, Tourmaline has a low melting point which requires that the stone be kept cool while cutting and faceting. Tourmaline crystallizes in the hexagonal system, as a prismatic crystal with a rounded, triangular cross section. Its colours are red (better known as rubellite, or akin to the colour of ruby), blue (or indicollite, as the colour suggests the colour of indigo), yellow, brown, green, black and colourless or parti-coloured. With a specific gravity of 3.0-3.1 and a refractive index of 1.62, it occurs in granite, pegmatite and metamorphic rocks. Tourmalines are found in Sri Lanka, Brazil, Mozambique, Maine, Malagasy, among other places.