If you break open a rough agate you might find a design that looks like a tree or a landscape, or you might see patterns and colors--each agate is unique. Find this variety of chalcedony (a form of quartz that has decorative concentric bands) worldwide from the shores of oceans to deserts. Agates can be discovered rough state or naturally polished in nature, and are available cut and polished through commercial vendors. They are considered a semiprecious stone.
Finding the Agate
Study the ancient geology of an area to find ancient lava flows. Agates formed in gas pockets within those flows. Throughout the centuries, the ground shifted, and weathering exposed them or freed them from the lava. Study the topography to see how weathering and water flow changed the landscape. They also formed wherever there was a hole in such places as coral and limestone.
Choose a time of year when there are storms. Agates are more likely to be exposed following a storm along coast lines and along rivers. Look where cliff erosion is occurring.
Research tables on tides when searching a beach area. This provides information on when the tide is low, giving you more space to look for agates. Also, high tides can push more sand around and expose more agates. Schedule a visit to hunt after the high tide.
Search maps to find areas known for agates. These can be such areas as the shoreline of Lake Superior in Minnesota or the coast line of Oregon. Place names can give an indication of where agates are found. Look for areas that offer recreational rock hunting.
Search beaches in areas known for agates. These finds may already be polished due to the action of the waves or from being carried downstream to the beach.
Look in areas where the land is being cut out. This can be a road cut, building construction or gravel pits.
Look for rocks that appear to have a waxy, grayish coating. The outer surface is rough, as though it was removed from a mold.
Look for rocks that have openings. This is where gas within the cavity where the agate formed would have escaped. Not all rough agates will have an opening.
Light the rock specimen using the flashlight. Hold the rock up and place it in front of the light. (The light from the sun can be used but make sure that you don’t look at the sun.) Check for bands and translucent rock.