Microbes are hypothesized to constrain the form, distribution, and abundance of lanthanides in granitic soils. In weathering, primary minerals are broken down, mobilising lanthanides into solution. Solubilized lanthanides precipitate with dissolved phosphate to form secondary minerals. Previous work has shown high microbial abundance correlates with lanthanide depletion, including observations of microbial cells attached to secondary lanthanide phosphate minerals. We have identified a Victorian granite soil profile exhibiting regions of lanthanide enrichment and depletion. SEM and trace element data revealed the formation of secondary lanthanide phosphate minerals less than 5um in size throughout the profile, including characteristic zones of enrichment and depletion. Our preliminary results have shown the common soil bacterium Pseudomonas putida KT2240, which contains a lanthanide dependent dehydrogenase, is capable of growing on synthesized lanthanum phosphate nanocrystals analogous to the secondary lanthanide phosphate minerals found in our site. By focusing on the interactions between soil microorganisms and lanthanide-phosphate minerals, our work seeks to understand how microbes break down these highly insoluble secondary minerals in the environment.