Sand Casting type Mushroom Anchor marine fittings. Black coating or red primer coating.
A mushroom anchor will normally sink in the silt to the point where it has displaced its own weight in bottom material,
Mushroom Anchor Castings
thus greatly increasing its holding power. As it can take time for the mushroom anchor to imbed itself into the seabed and achieve its full holding potential, it is often recommended (that if it is to be lifted when it is checked), that the timing of the check be coordinated to follow the stormy part of the season. These anchors are only suitable for a silt or mud bottom, since they rely upon suction and cohesion of the bottom material, which rocky or coarse sand bottoms lack. The holding power of this anchor is at best about twice its weight unless it becomes buried, when it can be as much as ten times its weight . They are available in sizes from about 10 lb up to several tons