It is believed they grow as the result of capillary action, as the water seeps from the rock and is then pulled along through tiny, internal canals within the depositing crystal structure instead of yielding to gravity. Nearly freestanding speleothems called shields are supposed to grow in a similar manner, but along hairline cracks in the bedrock, instead of circular pores. The cave shield in theOnondaga Cave Rock of Ages room is one of only a few in the United States. Cave pearls , are a fairly rare speleothem, formed similarly to a pearl, as a piece of sand or grit is rolled underwater, and coated on all sides with calcite. Constant movement of the pearl in a waterfilled depression keeps it from becoming attached to the bottom of the pool.
Cave pearls can grow to several inches in diameter.
It is harder than dolomite. Chert reveals itself as dark pendants, nodules, and reef structures, mostly noticeable in the cave ceiling. Wherever an irregular, dark brownish protrusion from the dolomite occurs, it is a good bet it is chert. Many of the rocks in the cave streams are chert gravel. Cave Clay .