Agate, also known as agate, Kate Ma and agate, is a kind of chalcedony mineral. It is usually a banded rock block mixed with opal and aphanitic. Its hardness is 6.5-7 degrees, its specific gravity is 2.65, and its color is quite layered. Translucent or opaque. The primitive form of tripartite crystal system. It is often dense and massive, forming various structures, such as breast, grape and tuberculosis. The common structure is concentric circles. Chalcedony has different colors, usually green, red, yellow, brown, white and so on. According to patterns and impurities, it can be divided into onyx, silk-wrapped agate, moss agate, castle agate and so on. Usually used as toys or decorations. Often used as an ornament or ornamental. Agate balls can often be seen in ancient funerary objects.

Obsidian (English name: Obsidian) is a common black gem and volcanic crystal, also known as "Dragon Crystal, Ten Victory Stones". This is a natural silica, usually black. Obsidian has been used as an evil spirit and amulet since ancient times. Obsidian can be processed into handicrafts. In addition, obsidian has the characteristics of glass, and its cross section is shell-shaped and very sharp. Obsidian is one of the gems used in Buddhism to make beads and handicrafts. In China's traditional folk customs, obsidian is usually combined with bravery to make various ornaments and ornaments, which can be worn and placed at home to attract wealth and ward off evil spirits. At present, most obsidian jewelry is produced in Central America and North America, and the national stone of Mexico is obsidian.