Where do I get this belief from? My own experiences plus reading about ancient knowledge and channeled material concerning stones.
A quote that seems to cover this is:

The reverence for stones, crystals and gems goes far back in humankind's history, necklaces, amulets and other adornments being found in burial sites as long ago as 25,000BC. Jewelry and goldwork of superb workmanship were found in the tomb of Queen Pu-Abi at Ur (west of the Euphrates) dated around 5,000 years ago. Psychics tell us that the Lemurians, Atlantians and Egyptians attributed great value to gems and stones, both for their ornamental and occult qualities.

Ancient astrologers (and many modern day ones also) told of connections between planets, birthdates and stones which they believed offered influences and various powers to the user by their vibrations and colors.

Mystics have classified the benefits of stones for differing problems over many centuries, offering them as healing tools. The ancient Vedic texts (in Sanskrit) have many stories of how the various stones were created. Also how and when to use gems and stones for protection, guidance and healing.

According to channellings by Edgar Cayce, gems' real value lies in the fact that they are 'essentially the same material as the soul'. Stones are enriched with decomposed matter and they in turn nourish the plants which feed and shelter us. Cayce's work gives great detail of how the ancient priests and seers used gems in breastplates they wore to aid their judgment and prophecy - their ability to 'listen' for God's guidance. Stones are mentioned many times in the Bible, including those adorning the foundation walls in The Revelation.

Today we are all using stones/gems either unconsciously or consciously. We all like to wear beautiful stones in jewelry; it makes us feel good wearing their beautiful colors and shapes. The stones' vibrations are able to work with us both physically and spiritually. Whether we are aware of this or not is immaterial.

Our entire material world is composed of atomic forces of matter as are our bodies, plus we have a spiritual body. Being created from the same material, we and stones have compatible vibrations. A stone's vibratory nature is determined by the minerals and elements it is composed of being arranged in a particular format. Thus there is a sympathetic vibration available between stones and us. When we and a stone are in accord, the extra vibrations of the stone increase our body's sensitivities, guiding us to consciously or unconsciously find answers to problems, to see our path more clearly, to make choices that benefit us and aid our healing physically, emotionally, mentally and spiritually.

Stones/gems/crystals are co-workers, friends and companions along our path of evolution and healing. Never give your own power away by thinking. 'It is the crystal that does it, not me.' Our attitudes influence our body's vibrations. Cayce felt that a stone would be beneficial when our attitude was correct but would never be detrimental. Internationally-known Lazaris (channeled by Jack Purcel) gives out crystals to his seminar participants. Lazaris states they are vibrational medicine for us, especially at this time in our evolution. The reason being, as we raise our consciousness and our vibrations by various spiritual practices, so we respond more quickly and effectively to the healing vibrations of stones, flowers, colors and sound. Aiding us to raise our vibrations also aids us to bring more divine light into our four-body system.

Where does this history and information leave a person just becoming interested in consciously working with stones and crystals? How to choose and care for stones is another question that arises.

Firstly: always choose your stone/crystal/gem with your 'inner sight' rather than because it appears to be the most beautiful one there. Close your eyes and hold your hand just above the stones and ask 'which is best for me?' You will feel/sense a reaction -- it may be a coolness, a hot spot, a tingle or your fingers will scoop up one stone. Always go with that first choice. There are many books you can read or people you can ask about your special stone and its benefits for you.

Second: you may read or be told about a particular stone and sense it would be good for you. Choose your particular stone for example, amethyst, from many amethystine the same manner outlines above. Always treat your stones with love and respect, thanking and cleansing them after working with or wearing them.

A quick and easy way to cleanse stones is with incense which is safe for all stones and minerals, whereas water is not. As you hold the stone in the smoke, ask that it be cleansed of all disharmony it has taken on in an effort to protect you and your environment. Ask that it be filled with unconditional love and to continue working with you for your mutual evolvement.

Quartz crystals are a good starting point for the beginner. There are several types and colors of quartz. All have the basic qualities of Clear Quartz, then added qualities due to the differing minerals that give them their color vibrations. Quartz is very stable and has a structure close to that of our DNA. Our modern technology is based upon quartz (silicon) because of this stability and its ability to amplify energies.

Clear Quartz contains piezoelectric and pyroelectric properties which support amplification, focusing, storing, transfer and transformation of energy. It amplifies our body's energies and our thoughts; provides clarity to our thinking; harmonizes and aligns our subtle bodies' energies; aligns the chakra system, thus leading to our healing occurring. Seen by many crystal therapists as a bridge between our mental and physical dimensions, it aids our connection with angels, guides, master teachers and healers. It can be used anywhere on the body at any time for any problem except for tumors. If the client has failed to process through the reasons for the illness/lesson, the last thing they need is amplification of the problem.

Rose Quartz, the ray of love, the cornerstone of the heart. It is good for everyone from conception to transition. It heals, calms and helps us to learn gentleness and compassion for self and others.

Amethyst Quartz is widely loved for its color which can be pale lavender to deep, deep purple. A stone of protection and spirituality, it transmutes low level energies to a higher, more spiritual level. The Churches us it in their clergymen's rings. It aids us with meditation, connects us with our own inner wisdom and helps us to work with our guides and ascended masters. Used for many centuries to bring feelings of hope, trust, truth and dignity to the user, it is often called 'the healer's stone.'

Sodalite, a silicate, is usually deep blue with creamy veins, however, it does appear in other colors occasionally. It is a wonderful stone for guarding against pollution on any level of our being, and protects against low level radiation, for example computers. At the Third Eye, it gently opens us to our natural psychic abilities. It eliminates confusion and aids logical thinking. At the throat, it encourages us to speak our truth and to release fear. It aids the thymus to release the judgmental energies placed there, and it strengthens the immune system.

Calcite, or calcium carbonate, comes in many colors, hues and shapes. A stone of change, it supports us, enabling us to view our behavior patterns and objectively decide if they aid or hinder us. It encourages us while we remove old, troublesome patterns to place in new patterns that serve us. Soothing and invigorating, its vibration teaches us that change is both possible and desirable on any level of our Being. It is a powerful friend in these transient times.

There are literally thousands of types of stones, and they all work beneficially for us. We will be drawn to one for perhaps many days, even months, and then towards another, that shows our progress in healing ourselves and our growth spiritually.

When you allow one stone into your life it will usually be quickly followed by several more friends. They are a joy to live with and to work with.

Reprinted with the kind permission of Golden Age magazine.