The Fun Variety of Agates!
Agates are fun for so many reasons! They are common and abundant and can be collected almost anywhere.
No matter where you live, there is probably an agate field within easy reach for a day trip. Their abundance also makes most agates inexpensive at rock shops and gem shows. In addition, they can be enjoyed “as is” or cut, crafted, and tumblepolished into lapidary wonders.
Thus, agate is a perfect stone for the beginning collector.
For me, the best thing about agates is the great variety they show in colors and patterns. Agates precipitate out of solution and grow in seams within other rocks or within vesicles in basalt or cavities within limestone, later eroding out as nodules.
An agate may grow as an undifferentiated mass.
It may be all one color, or it may have inclusions or colorful concentric bands.
Consider just a few of the many varieties:
Fortification agates have concentric bands that look much like a “fort” circling a castle. Water line (or water level) agates have straight bands that formed by gravity as layer after layer of agate was set down. Eye agates have spots on the surface. Flame and plume agates are very similar. Flame agates have swirling red lines that look like fire, whereas plume agates have interesting inclusions that look like ferns or plumes of smoke.
Similarly, sagenitic agates have inclusions, but these are needle-shaped. Moss agates are similar to plume agates, but the plumes permeate the entire rock, often in shades of green, brown, yellow, or red.
In addition, there are shadow, tube, seam, polyhedral, enhydro, fire, iris, and many more varieties of agates. This wonderful variety makes agates a whole lot of fun to collect!
Look through agates in your own collection. How many varieties can you spot?