I replaced the picture I originally posted here with one that more accurately represents the true color. It is crystal clear and simply gorgeous.
There is an area of the Park where there are several “basins” holding a variety of geysers, mud pots, fumaroles, hot springs and other interesting hydrothermal features. There is a very strong sulphur (rotten egg) odor present when you are near these basins.
It is hard to capture the beauty and character of these various things with still pictures. I did take short video clips of many of them and will share them when I get home. I waited almost an hour and a half to watch Old Faithful erupt and have video of it. It erupts every 35 to 120 minutes and evidently I got there shortly after it had just done so, so had to wait what turned out to be more towards the longer end of the range.