|Minerals and other growths at Sulphur Works.|
|A somewhat closer view of crystals in the upper right of the first photo.|
|Greenish yellow crystals from the lower left of the first photo.|
|Close up of pointed, needle-like crystals.|
Photo examples of similar Sulfur crystals: 1) elongated crystals from the Jemez Mountains, NM, and 2) needle-like crystals at TheodoreGray.com, also shown here.
So, is it Sulfur or something else?
UPDATE 14Oct2012: In the comments, Ron Schott added a similar picture of Sulfur crystals from a fumarole at Nisyros Volcano, Greece, if anything, even more needle-like than these.
Mud Pot at Sulphur Works
Fumarole at Sulphur Works
Views of Lassen