Manganese induce a strong green color in glass by forming less-colored iron(III) and slightly pink manganese(II), compensating for the residual color of the iron(III). Larger quantities of manganese are used to produce pink colored glass. Tetravalent manganese is used as an activator in red-emitting phosphors. While many compounds are known which show luminescence the majority is not used in commercial application due to low efficiency or deep red emission. However, several Mn aktivated fluorides were reported as potential red emitting phorshors for warm-white LEDs. But to this day, only KSiF:Mn is commercially available for use in warm-white LEDs. The manganese oxide
SS Manganese was sold to the Sinai Manganese Co, Egypt and was renamed "Manganese". The ship was deleted from Lloyd's Register in 1993. SS Manganese Manganese was a coaster that was built in 1925 by Norderwerft AG, Hamburg, Germany as Wiedau for German owners. She was seized by the Allies in May 1945, passed to the Ministry of War Transport (MoWT) and was renamed Empire Contract. Later that year, she was transferred to Greece and renamed "Herakleion". She was sold into merchant service in 1948 and renamed Laconia. In 1965, she was sold to Egypt and renamed "Manganese". The ship was deleted