Apatite is one of the most common accessory minerals. It takes part in the structure of all types of rocks, mainly on their trace elements. Because of that, apatite is an important indicative in geochemistry comprehensiveness of the earth it occurs. In addition, it provides significant information regarding the source rock and its remaining conditions during the crystallization process – such as oxygen fugacity and magma luminosity. Due to its capacity of incorporating important elements such as Na, K, Mn, F, Cl, Sr, Pb, Th, U, V, As, S, Y in its structure as well as rare earth elements, apatite is described as a mineral with potential for exploitation of mineral deposits. Geochemical signature of tin granites was prepared using the apatite chemical and morphologic characteristics to compose a set of Resistate Indicator Mineral (RIM). Among other mineralized plutons, the Antônio Vicente Granite (1,88 Ga) integrates the South Tin Province of Pará. In this regard, apatites from mineralized facies were analyzed through the MEV-EDS method. The results showed richness of Rb, Sr, Y, F and ETRP and lower content of Ca. This expresses direct relation with conditions of crystallization and late fluid percolation of post-magmatic that generated the mineralization. Back cattereo images of apatite werw done in MEV, which made possible to identify important internal features of the mineral such as zoning, inclusions and alteration indicative features. To compare the results, this study used: Redenção Granite and Jamon Granite (1,88 Ga), São Jorge Jovem Granite (1,88 Ga) and finally Suíte Sanukitoide Rio Maria (2,87 Ga). Each one of the granites presented a different morphology then the Antônio Vicente’s apatite. Usually they are euhedral to subhefral, with other mineral inclusions as well as zoned. Also presenting in its composition Ca enrichment and low traces of rare earth elements in relation to the most developed facies.
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