The seven colors are usually associated with certain gemstones or beads. These correlate to the 7 major chakras in our body. Typically, there are seven major chakras.
The Root or Base: Red. Gemstones include red jasper.
The Naval or Sacral: Orange. Gemstones include Orange Zincite.
The Solar Plexus: Yellow. Gemstones includes Yellow Topaz or Citrine
The Heart: Green. Gemstones include Green Tourmaline or Aventurine
The Throat: Blue. Gemstones include Turquoise.
The Brow or 3rd Eye: Indigo. Gemstones includes Lapis Lazuli.
The Crown: Purple or Clear/White. Gemstones include Amethyst.