Sapphire glass is known in the luxury watch world as the definitive material for transparency and durability. Sapphire is a synthetic crystal (aluminum oxide Al2O3) rather than actual glass. It is colorless and optically clear. Mechanically, it is second only to diamond as the hardest and most scratch resistant materials on earth. It also has a very high modulus of elasticity and tensile strength, making it extremely versatile and resistant to impact/abrasion. JORD stays true to their mission of quality and craftsmanship by incorporating this same glass in many of our premium timepieces.