- Rhodonite is a manganese inosilicate, with the formula (Mn, Fe, Mg, Ca)SiO3, and member of the pyroxenoid group of minerals, crystallizing in the triclinic system. It commonly occurs as cleavable to compact masses with a rose-red color (its name comes from Ancient Greek ῥόδον (rhódon) ‘rose’), often tending to brown due to surface oxidation. The rose-red hue is caused by the manganese cation (Mn2+).
- Saint Anthony Falls (Wikipedia)
Saint Anthony Falls, or the Falls of Saint Anthony (Dakota: Owámniyomni, lit. ‘whirlpool’), located at the northeastern edge of downtown Minneapolis, Minnesota, is the only natural major waterfall on the Mississippi River. Throughout the mid-to-late 1800s, various dams were built atop the east and west faces of the falls to support the milling industry that spurred the growth of the city of Minneapolis. In 1880, the central face of the falls was reinforced with a sloping timber apron to stop the upstream erosion of the falls. In the 1950s, the apron was rebuilt with concrete, which makes up the most visible portion of the falls today. A series of locks were constructed in the 1950s and 1960s to extend navigation to points upstream.