Abstract: A lightweight aluminum anchor for marine vessels having removable flukes loosely coupled to an improved monolithic crown structure that has the same holding power as heavier, though similarly sized, steel anchors, yet is easily retrieved when it is no longer necessary to secure the vessel. The monolithic crown structure has oppositely disposed angled side walls integrally merging into the crown plates, resulting in the crown plates having a thicker and stronger center portion so that operational stresses of the anchor may be incurred without deforming the crown structure. Inset in each side wall is a fluke coupling member to which the flukes are attached that reduces the interior volume of the crown structure. The reduction of interior volume reduces the possible accumulation of debris, thereby making retrieval of the anchor much easier. Since all components of the anchor are made from extruded aluminum, no welding is required to assemble the anchor.