The authentic crystals are:

• Red Agate for Root/Base Chakra
• Red Aventurine for Sacral Chakra
• Citrine for Solar Plexus Chakra
• Green Aventurine for Heart Chakra
• Blue Turquoise for Throat Chakra
• Amethyst Third Eye/Brow Chakra
• Selenite for Crown Chakra

They're sized at 8mm genuine crystal beads with 13 pieces of Lava Stones.

• Use a flexible or cloth measuring tape to measure your wrist size.
• If you prefer a looser fit, go down a 1/2 inch or more from your wrist measurement.
• For a snug fit, use your exact wrist measurement.
• If you don't have a flexible measuring tape, you can also use a piece of string or ribbon and measure it against a ruler.
• Keep in mind that the size of the beads (8mm in this case) and other details of the bracelet may also affect the fit.