monomagnesium phosphate u201c mop u201d to make a cementitious material the cementitious material can be used in essentially any way that other building materials such as wood or cement blocks are used building blocks and fence posts are among the most preferred commercial embodiments the invention finds particular advantage in its ability to use recycled or waste wood chips as the fiber material in some less preferred embodiments new or recycled paper may be used in addition to or as a replacement for the wood chips alternatively other synthetic or natural water absorbent fillers may be used to supplement or replace the wood or paper fibers although those embodiments are less preferred in testing to date for the remainder of this disclosure wood chips will generally be used as the water absorbent fiber material it is to be understood though that other fibers could be used as noted above the wood chips or other water absorbent fibrous material is preferably sized between u201c mulch u201d sized chips and wood u201c shavings u201d most commonly a majority of the wood chip material is provided by chips that are between about 0 50 u2033 and 1 50 u2033 in length 12 to 38 mm with chips between 0 50 u2033 and 1 0 u2033 long being more preferred similarly a substantial portion of the wood chip material is provided by chips that are between about 0 125 u2033 to 0 50 u2033 thick 3 to 12 mm with chips between 0 125 u2033 and 0 25 u2033 thick being more preferred lastly a substantial portion of the wood chip material is provided by chips that are between about 0 125 u2033.