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Rhodonite tends to be pink, rose-red to brownish red in color and is known as the "Rose Stone" in Taiwan. Hardness is between 5.5 and 6 .5 on the Mohs scale with a specific gravity of 3.55 to 3.76. White striations are present and there usually white stripes or black manganese oxide patches on the inside. In Taiwan, rhodonite is mainly found around the Simaoshan, and Liwu, Mugua and Sanjhan Rivers in Hualien County. Companion minerals such as pyroxmangite, quartz, rhodochrosite, pyrolusite and hausmannite are usually present. Most rhodonite is used as ornamental rock or processed into jewelry.

Mineral Formation
Rhodonite is formed from manganese-rich sediments in ancient seas that were pushed to the surface by tectonic movement then subjected to regional alteration. 

Geographic Distribution
Found in the layered manganese deposits at Simaoshan, Liwu River, Mugua River and Sanjhan River around Dong-ao. 

Mining History
Rhodonite had been discovered in Taiwan during the Japanese colonial period. Mitsuo Ogasawara discovered manganese deposits containing rhodonite at Simaoshan in Dong-ao in 1931. Manganese extraction technology was still very primitive so there was no large-scale mining. More rhodonite was found in other Hualien river valleys later on and Sanjhan River became known as "Rose River". By the 1980's, rhodonite had become a popular ornamental rock though most were collected by private individuals and it was not mined as a gemstone on an official basis. Years of prospecting depleted the sources of rhodonite and it began fetching higher prices due to its rarity, leading to constant illegal mining.

Most rhodonite sources now lie within the Taroko National Park so mining and collection is banned by national park law. 
Rhodonite that is pink to rose-red in color with black manganese oxide patterns is often used as ornamental rock, decoration or artwork.

National Museum of Natural Science