@ JohnG
Synthetic saphire does not mean mineral glass, no matter what lies the dealers use, synthetic saphire is what you will find on any watch fitted with saphire glass. from a tisot to a rolex to a patek,
Sapphire refers to gem varieties of the mineral corundum, an aluminium oxide (Al2O3), when it is a color other than red. Sapphire can be found naturally or manufactured in large crystal boules. Because of its remarkable hardness sapphire is used in many applications, including infrared optical components, watch crystals, high-durability windows, and wafers for the deposition of semiconductors, such as GaN nanorods.
The mineral corundum consists of pure aluminium oxide. Trace amounts of other elements such as iron, titanium and chromium give corundum their blue, yellow, pink, purple, orange or greenish color. Sapphire includes any gemstone quality varieties of the mineral corundum except the fully saturated red variety, which is instead known as ruby, and the pinkish-orange variety known as padparadscha.
Some dealers do missrepresent there wears but do not take it as read that any one that uses the wording "Synthetic Saphire" is ripping you off.