As Grizzly Bears age, they gain greyish white tips on the dark shoulder hairs and around their head and ears. This is the grizzled or frosted look, and they have the nickname of silvertip. There are no entire white hairs, just the tips are...
After finally being diagnosed, I went on Pyridium - it actually got rid of the pain! So, I only use it for flareups. However, I've found that when the pain is really bad, it is just moderated. Have taken Pyridium for 3-4 weeks straight without side effects except mild stomach upset if taken without food.
Pure iridium is very brittle and is nearly impossible to machine. It is primarily used as a hardening agent for platinum. Platinum-iridium alloys are used to make crucibles and other high temperature equipment. Iridium is also alloyed with osmium to make the tips of fountain pens and compass bearings.