made of FeO with P2O5 making up almost the same weight percentage. There is a significant percentage of the Na2O oxide and an insignificant percentage of the CaO oxide (~0). It is clear from looking at the oxide content of the mineral that the main components are going to be sodium, iron, phosphorus, and oxygen. The oxide factor may be used to determine the weight percentages of the individual elements as follows, 1 sodium atom totaling ~13% of composition, 1 iron atom totaling ~32% of composition, 1 phosphorus atom totaling ~18% of composition, and 4 oxygen atoms totaling ~37% of composition (Sturman, et al., 1977). Structure Maricite is an ionic double metal phosphate, with a space filling capacity of about 70% (Le Page, and Donnay, 1977). The structure of maricite contains a sodium cation enclosed by ten oxygen anions within 10 Å, in an irregular coordination. There is (2+2+2) type distorted tetrahedron around the iron (Bridson, et al., 1997). The Å distances between iron and oxygen are between 2.33 and 2.93. The phosphate tetrahedron is almost regular, with 2 short bonds and 2 longer bonds (Bridson, et al., 1997). The iron atom has four surrounding oxygen atoms giving it tetrahedral coordination. Half of the oxygen atoms are coordinated with two sodium atoms, two iron atoms, and one phosphorus atom while the other half are coordinated with three sodium atoms, one iron atom and one phosphorus atom (Bridson, et al., 1997). The structure of maricite has been compared to the structure of olivine, (Lee, et al., 2011). The structures of the two minerals are similar because they both contain PO4 in their atomic make-up (Moreau, et al., 2010). However, the M1 and M2 sites for LiFePO4 and NaFePO4 have reverse occupancies making their structures different (Lee, et al., 2011). In olivine, the M1 site holds the alkali metal while the M2 site holds the transition metal, whereas in maricite, the M1 site holds the transition metal and the M2 site holds the alkali metal (Ong, et al., 2011). Physical properties Maricite (NaFePO4), is found in elongated grains up to 15 cm long in the [100] direction. The grains are radial to sub parallel in structure. Maricite is usually colorless to gray, but is sometimes a pale brown color and it has a white streak. It has a vitreous luster due to its low values of refractive indices, α = 1.676 β