But now, instead of enlarging the cavern, the mineral-rich fluid began filling it once again. Drop by drop, over centuries, seemingly insignificant trickles worked wonders in stone. The result is a rich display of cave formations, or as scientists call them, speleothems. Lehman Caves contains familiar structures such as stalactites, stalagmites, columns, draperies, and flowstone, along with some interesting and delicate rarities. Lehman Caves is most famous for the rare and mysterious structures called shields .
Shields consist of two roughly circular halves, almost like flattened clam shells.
How they are formed remains a subject of controversy - another of the pleasant mysteries to be found in the underground world. Helectites look like forests of chow mein noodles. Aragonite grows clusters of snow-white needles. Cave popcorn , looking like its namesake, adorns many walls.