It has been a common practice of cultures worldwide to use talismans (or amulets) as an object of luck or protection. A talisman can be simple or intricate, made of such items as gems, stones, statues, pendants, rings, plants or animals. The most commonly employed talismans are those that can be carried on a person's body as that keeps the aura of luck or protection close at hand.

The Christian cross and Judaic Star of David is two obvious examples of talismans. Some Buddhists will put a figure of the Buddha on a chain and wear it around their necks. Voodoo cultures give weight to what color of candles they light as each hue has a different talisman property of attraction or repulsion.

But a talisman isn't always tied to religion. A rabbit's foot and four leaf clover are widely recognized tokens of luck. When villagers in Central Europe believed in the existence of vampires, the protective talismans of crucifixes and garlic were employed and have remained entrenched in the horror genre since.
Ancient Egypt is still remembered for its use of the symbol of the ankh and scarab as amulets.

Numerology has associated magic squares based on astrology that each can provide a unique strength as a talisman. There are seven squares total that are represented by a different celestial body- Saturn, Jupiter, Mars, the Sun, Venus, Mercury or the Moon. The talisman powers associated with these squares
range from the standard protection and luck to healing and the collection of energy.

Each symbol of the zodiac has gems corresponding to it that can act as a talisman. Amethyst, amber and aquamarine are a few of the gems that relate to Pisces. Aquarius is associated with garnet, hematite and turquoise. Capricorn's should carry ruby or agate. Sagittarian archers can equip themselves with jasper or
tourmaline. Jasper is also good for Scorpios- as are ruby and aquamarine. Libra corresponds to emerald and coral, Virgo to peridot and rhodochrosite, Leo to citrine and onyx, Cancer to moonstone or aventurine, Gemini to tiger eye or agate, Taurus to sapphire or azurite and Aries to malachite or rose quartz. 
Many stones (and gemstones) have powers attributed to them. Emeralds are thought to bring love, happiness and wealth. If you are about to take a trip, pack some rhodonite as it is a talisman of safe travel. Jade is believed to attract energy to the bearer. A ruby can bring about balance. Onyx can alleviate
pain and trouble. Malachite is believed to provide protection and bond one with the earth.

Crystals are also commonly employed as a talisman. Amethyst can bestow wealth, love and happiness. Rose quartz is carried for protection and to keep the energy around the bearer positive. Natural quartz is also utilized for its energy. Both crystals and stones are often carried in pouches in a combination that
best suits the carrier's talisman needs. 

Is there any scientific proof that talismans or amulets really have any effect? No, but there isn't any proof that they don't. Meditation is similarly in the mind and has recordable physiological effects. Believing in something firmly enough is often enough for it to become the truth- and carrying a pocketful of gems certainly isn't going to hurt anyone.