An uplifting stone, amethyst is said to strengthen intuitive abilities and help disperse negativity. Communication can be made easier by the presence of amethyst, and if you are having trouble sleeping, it is thought to promote easy sleep and good dreams. It can also be helpful in combating headaches and hangovers!
Black pearls are a relatively rare thing. Pearls are not actually stones; rather, they are formed by oysters coating foreign bodies within their shells with nacre, which in time and with sufficient coats forms a pearl. As a darker form of the ordinary pearl, perhaps the attributes of pearls could be applied only with a darker edge....
Carnelian is an agate. As such it has a reputation for promoting strength, enhancing creativity and the thought process. It is also thought to promote success, so if you're up for promotion, this could be the stone for you.
Garnet was used in the thirteenth century as an insect repellant. This might not have persisted, but garnet still has a reputation as a repellant. However, modern thought dwells more on the repulsion of depression, infection and skin disease. Garnet is thought to encourage determination and energy, whilst bringing out courage and attracting love.
Haematite is an interesting and unusual-looking stone; indeed, it could almost pass for a metal due to its dark glossy appearance. It is thought to strengthen the heart and lower a rapid pulse, and is also associated with improving the blood. On an emotional level, haematite is said to help insomnia, problems associated with air travel, concentration and focus.
Iolite is also known as the Water Sapphire, a name it acquired in Victorian times because of its colour. Iolite can look violet blue - almost speedwell-coloured - hence its association with the sapphire, but at the same time it can seem brownish or transparent and clear, reflecting the Victorian idea of it as water-like. Iolite is comparatively rare and is thought to help one stand up for oneself, inducing courage and emotional control and encouraging intuitive ability and self-healing.
Jade is often thought of as a relaxation stone. This is perhaps linked with its pretty green colour - green is supposedly the colour that is easiest on the eyes, and when our eyes are tired from computer screens or whatever, looking out at the greenery of nature may help. Alternatively, if that's not an option, perhaps jade is the answer. Jade is one of the Chinese symbols of good luck, and is also thought to encourage longevity and wisdom.
Labradorite is said to protect the aura, and is associated with strength and perseverance. Its symbol is the moon, and it is thought to help adjust to changes, perhaps reflecting the constantly changing phases of the moon. It relieves insecurity and apprehension and encourages patience, originality and precision. It also has a reputation for aiding the digestion and the eyes.
Moonstone, "the Traveller's Stone", comes in several colours, all of which are soft. This softness reflects its qualities - Moonstone is associated with compassion, love and sympathy, and has a reputation for helping lovers overcome their differences. On a more unusual note, it is also thought to encourage psychic powers, and can help prevent nightmares when placed under a pillow. Moonstone is also thought to help overcome the symptoms of P.M.T, perhaps because of the link between women and the moon and its beautiful sheen and moon-like appearance.
Pearls can help one to accept love, and encourage self-acceptance. The pearl is not a stone, but is formed by the oyster (see also black pearls, above). Pearls are traditionally associated with sorrow, "pearls for sorrow", but it is not clear whether this association means they prevent it or alleviate it when you're already sorry! Pearls are thought to ease childbirth and increase fertility whilst encouraging faith, charity, integrity and truth. It has also been suggested that pearls can help encourage the formation of antibodies and bolster the immune system.
Quartz crystals have a variety of associations. They are often thought of as something to absorb negativity, working as a sort of shield. Quartz can help free the mind from trivia, allowing a deeper meditative state, if that's something you're into. It is thought that a quartz crystal can be "charged" with positive thoughts or a particular wish, and that wearing the crystal after it's been charged, or keeping it close to you, may help to bring about that wish. Once charged, they can also be useful in bringing about particular dreams when kept under your pillow. Quartz crystals are representative of elemental wholeness and are said to show the synergy of yin and yang.
Rose quartz is said to promote tranquillity and love, reflecting its pale pink colour. It is also thought to promote love of both self and others (though not in the sense of vanity!) and to soothe away irritations and frustrations. It is also excellent for helping grief and loss or other emotional trauma, and is said to hasten recovery from both emotional and physical harm.