Natural spinel in marble 108.2g, Vietnam

Spinels from Vietnam are similar in composition to other spinels, with the chemical formula being MgAl2O4. It is therefore a mineral in which magnesium (Mg) and aluminum (Al) are combined with oxygen (O). This formula applies to all spinels, regardless of their place of origin. Spinels are metal oxide minerals and are known for their diverse color palette that includes red, pink, blue, purple, yellow, orange, green and black. Each color of spinel is caused by the presence of different impurities and trace elements. Spinels from Vietnam are mainly characterized by red and pink color, which often resembles ruby and pink sapphire. This color is due to the inclusion of chromium or iron in the spinel.


The spinel deposits of Cong Troi (sometimes also known as Công Trới) are located in the Yên Bái province of Vietnam. Cong Troi is known for its rich resources of natural spinels, especially red and pink spinels. Spinels from Cong Troi are often of high quality and are sought after gems on the market. The red and pink spinels from this area are prized for their intense color, especially the red, which often resembles the color of a ruby.