1. Tourmaline can be divided into green, red, blue and other types according to color, among which blue and red tourmalines have the highest value.

2. In addition, pure blue tourmaline is also of high value, among which watermelon red is the best and green tourmaline is the best.

3. Pay attention to the transparency of tourmaline after determining its color. The better the quality, the higher the transparency, while the poor quality tourmaline will have cotton-wool ice cracks inside, so it is not recommended to buy it.