Topaz is an extremely sturdy stone with a Mohs hardness of eight. Diamond, ruby and sapphire are the only commonly utilised gemstones using a bigger hardness. Two are pink and green bicolor stones generally known as "watermelon tourmaline." Bicolor and pleochroic tourmalines are favored stones of numerous jewelry designers mainly https://www.gemsbiz.com/blog/explore/the-july-birthstone-ruby