This elegant silver & white Date Just ladies Rolex comes with Roman Numerals on the dial, a white gold bezel in keeping with the white & silver colour way & of course all the fantastic quality associated with this archetypal br&. The sapphire glass is extremely hard wearing, & one of the reasons Rolex watches retain their value. We are often asked if there is a test for sapphire glass & all sorts of myths abound: licking it or letting drops of water fall on it amongst many others! There is a simple scientific test that jewellers can perform: a h&-held diamond tester checks the thermal conductivity & the result is displayed on a scale.