An OLD-TIME collection of 5, tan, orthorhombic boracite crystals to 4 mm mounted on a glass, microscope cover slip from the Type Locality, Kalkberg Hill, Luneberg, Lower Saxony, Germany. Boracite is a very rare manganese, boron chloride found in evaporate deposits. The largest crystal is loose in the old, wax envelope. Ex Richard Hauck Collection. 5 pieces 4 mm - largest