A great example of rhodochrosite from Japan, displaying the typical botryoidal habit.
The color does vary a bit with lighting-- you get the best color under incandescent lighting. What you see pictured is pretty much the worse color you will get out if it....
The Oppu mine was intermittently worked for various ore between the 1600's and closure 1979, with a final smaller scale operation undertaken int he 1980's to recover lapidary rhodochrosite. There is not a whole lot of this material around anymore, and it tends to be somewhat larger-- smaller, more manageably sized specimens like this are something of a rarity.