Opal is a gemstone with a color-changing effect. Pliny, a famous natural scientist in ancient Rome, once described it as follows: “On an opal stone, tu peux voir la flamme du rubis, les taches de couleur comme l'améthyste, and the emerald sea. Vert, the five colors are colorful, blending together, and beautiful.” Dans la Chine ancienne, opale […]
