Painite is a very rare borate mineral. Ruby is characteristic for its bright red color and is one of the most famous red precious stones. Large rubies are even rarer than diamonds. The oldest written records speak of mines in Myanmar. From there, he took trade routes to the royal courts and to the temples of ancient Egypt and Greece. In the Middle Ages, ruby was popular in Rome and the church as a symbol of blood. It was considered a stone of life that strengthens the heart and restores strength. In antiquity and the Middle Ages, he protected believers from the devil and protects them from the plague.