Moss Agate is a form of Chalcedony with embedded green minerals formed from oxidised Iron, Manganese and other elements. These green strands in the stone have the appearance of moss-like tendrils. It is not a true agate as it lacks agate banding.
In Madagascar there is a significant variation, commonly called Ocean Moss Agate. This stone features mostly soft blues, instead of the predominant milky-white of Moss Agate.
Location: Brazil, India, Madagascar, Uraguay, USA, Yemen
