1. A common silicate mineral of the mica group, typically brown or reddish-brown in color, used in electrical insulation and heat-resistant applications.
Usage: technical; mineralogy

Examples

• Phlogopite is valued in the manufacturing of electrical insulators because of its heat resistance.
• The geologist identified phlogopite crystals in the metamorphic rock sample.
• Phlogopite mica sheets are used in high-temperature applications such as furnace windows.
• The brown mineral phlogopite contains magnesium and potassium in its crystal structure.
• Industrial suppliers mine phlogopite for use in cosmetics and automotive gaskets.