2019年9月17日 Rose quartz and amethyst, tourmaline and citrine, labradorite and carnelian: Madagascar has them all Gems and precious metals were the country’s
2019年7月10日 Quartz also has a white streak (ie the color of the mineral when it is in a powdered form) In terms of hardness, quartz is relatively hard for a mineral and has a Moh’s scale hardness of 7 (out 10 – with