Instead of adorning its timepieces with precious stones, Swiss watch brand Louis Moinet uses dials made of polished stone for its Treasures of the World Collection (www.louismoinet.com). Australian opal and brown Biggs jasper are among the stones that specialist Daniel Haas cuts to form the dials. The collection also includes a one-of-a-kind Vertalis Tourbillon with a dial made of red stromatolite. Stromatolite is petrified blue-green algae, which is among the first-known life-forms on Earth. The material is extremely brittle, providing a challenging test of Haas’s stonecutting skills. The $245,000 Vertalis also features a well-finished Concepto tourbillon movement and a case with 18-karat red and white gold.