Proustite is a beautiful and rare mineral that is primarily found in high-temperature hydrothermal veins. It is composed of silver, arsenic, and sulfur. This mineral has several synonyms, including ruby silver, light red silver ore, pyrargyrite, and red silver. Proustite is a common secondary mineral in silver mines, and it is often associated with other minerals like calcite, pyrite, quartz, and galena. This mineral has a distinctive deep-red color and is highly sought-after by mineral collectors and jewelers. Proustite is named after French chemist, Louis Proust, who was one of the first scientists to study this mineral in the early 19th century.