Stone That Is a Symbol of Templars
This stone was considered sacred by members of the most mysterious medieval order - the Knights Templar. It comes as no surprise since the rock may change its colour in a matter of a few minutes.
Andalusite's name derives from Andalusia (Spanish: Andalucía), the southernmost part of Spain. Yet humanity had been aware of the mineral's existence long before it was unveiled officially. Back then it was more known as "cross-stone", which is, in fact, a non-transparent variety of andalusite.
The stone became most widespread in the Middle Ages, particularly among Templar Knights who used it to make rings and amulets. They believed the mineral was soaked with drops of Christ's blood and could protect those having it on them from battle injuries. The explanation is that the earlier mentioned variety, named chiastolite, commonly contains inclusions forming a cruciform pattern when shown in cross-section. The resulting image thereby heavily resembled the official symbol of the Templars.
The Order of Malta's representatives attributed magical features to andalusite, whereas alchemists were keen on its unusual outward appearance. There is a legend that Nostradamus, a worldwide known French seer, favoured the mineral, too. According to the legend, he had numerous jewel items with andalusite, including several rings, a pendant, and beads.
A notable characteristic of andalusite is the ability to change colour. Unlike alexandrite, which can do likewise, andalusite does not require a change in light to become of a different shade but a slope angle to be altered. Because of this peculiarity, the mineral was sometimes referred to as "poor man's alexandrite".
The mineral is widely spread across the world. However, there are few deposits of gem-quality andalusite. Stone samples vary in colour a lot: from warm shades of yellow and golden-yellow to grey and grey-brown. Colourless specimens are quite rare nonetheless. In jewellery, highly transparent samples are of more value.
Despite looking fancy, andalusite has more uses outside of the jewellery industry. It is commonly used as a refractory due to being able to withstand temperatures of up to 1850 degrees Celsius. Finally, the mineral is applied in the production of, for instance, spark plugs.