Apatite, monazite and allanite; three rare earth minerals from Korsnäs, Finland

In the AE-bearing lead deposit of Korsnäs, apatite is the most common REmineral, monazite is a widespread accessory and allanite is a rare constituent.The paper describes one type of each.Also, the physical properties and chemical composition of the minerals are presented.The chemical analyses contain determinations of the main components, trace elements and distribution of the rare earths.Light rare earths abound in each mineral, but slight differences can be observed in fractionation.