Usually the diamond is one carat or less. Some big hospitals even stamp information such as a patient's name, medication, timings, etc on the rubber band bracelets. In fact, it was Armstrong's 'LiveStrong' custom rubber bracelets that kicked off the trend of wearing rubber bracelets.
Explanation of Cut, Color and Clarity of This Diamond
Cut Quality The ideal cut diamond is a very precise mathematical equation, where diamond proportions and angles are cut to optimize the diamond's superlative optical properties, in particular it's high refractive index and color dispersion, to create a diamond of unequaled beauty with perfect balance of brilliance and fire. In layman's terms, the diamond is cut to make it the most beautiful diamond so it retains its intrinsic value.
Color An E color diamond is extremely rare and slightly less expensive than a D but is so similar that most people won’t be able to tell the difference. You pay a serious premium for an E color diamond. Diamonds of this color grade will appear colorless even when observed face down.
Clarity Diamonds of SI3 clarity are on a borderline between slightly included and included diamonds. SI3 grade inclusions are almost obvious under 10x magnification. Inclusions in such diamonds may be noticeable to the unaided eye. However, when observing the diamond "face up" as it is mounted in a ring, the inclusions are usually not visible.