IRIDESCENT MARCASITE Sweetwater Mine Reynolds County Missouri 3.5 x 2.3 x 1.2 Inches 9 x 6 x 3 Centimeters Small Cabinet This is a really cool specimen from a recent small find in the Sweetwater Mine. It is essentially a stalactite formation that is a bit deformed revealing the internal hollow structure. Add in the beautiful iridescence and the result is a very unusual and captivation specimen! I photographed it under pretty intense lighting to get the best possible look into the tubes/cavities and iridescence.