This Gem Is Like Quartz, but a Lot Wetter

If it weren’t for my high water content (anywhere between 3-20 percent), they say I’d basically be quartz. Which to me is like saying that if Lake Superior didn’t have water it’d be a prairie. Huh! A lake is a lake and quartz I am not. What I am is a soft, delicate, HYDRATED silicate of a certain healthy hue that is sometimes referred to as quinzite (and which yes OK, under some conditions can look like quartz).
Who am I?