TL;DR“The Gem” is a smart pendant that tracks sun exposure and provides real-time data on your skin health.It also tracks UVA and UVB exposure and tells you how long you can stay out before you get sunburn.It’s available for an introductory price of $199.We’re surrounded by gadgets that seem to want to help track everything about our fitness levels. Smartwatches track your steps, heart rate, blood oxygen levels, and can even take ECG readings. However, this new wearable wants to do something different: track your skin health and sun exposure.That’s the main idea behind The90’s new pendant (via Notebookcheck). It’s called The Gem, and it looks like a normal pendant one might wear as jewelry. However, it has a sensor inside its titanium case that measures the amount of UVA and UVB radiation hitting your skin.