Types of Anchors: Stone Anchors

Stone anchors were, almost certainly, the earliest type of anchor to be used, and continued in use for a very long time, indeed there are some types that are in use today. For this reason the dating of stone anchors is immensely difficult. Any dated examples are, potentially, of considerable importance so it is vital that any dating information be recorded. Most stone anchors are, in fact, composite anchors, in which the stone provided the weight to take the anchor to the sea bed, whilst the holding power was provided by means of separate arms, usually made of wood. Should any trace of the arms survive this too needs to be recorded. Complete wooden anchors may be found, they come in a variety of shapes and forms. They should be photographed and measurements taken.

Buoy and mooring anchors

Stone anchors were used for buoy and mooring anchors, usually simple weights, but it is possible that more complex types were used in the past.

Fishing gear

Stones have been, and in some places still are, used to sink nets, lines and other fishing gear. In many cases the only difference between these and some types of stone anchors is size, in fact it may be impossible to tell the difference between a large gear weight and a small boat anchor. Similar stones have also been used for more unusual purposes, such as driving fish into nets by beating them on the water. At present there is insufficient evidence to be able to separate these various uses of stone weights, for this reason all such stones, of whatever size, should be recorded.

Recycled stones

There is plenty of evidence that objects have been reused as stone anchors and fishing weights. This must be recognized as it could lead to problems when it comes to ascribing a date to an anchor, or recognizing an object as an anchor. Quern and mill stones can be recycled as anchors, so the discovery of such a stone on the sea bed need not be evidence of it having been carried as cargo.


Stone anchors have been found with a variety of inscriptions, these range from an elaborate carving of an octopus to simple symbols. Carvings can sometimes provide evidence of date, a Christian cross, for example, must post date the introduction of Christianity to the area.
So far some five basic types of stone anchor have been recorded throughout the world. There are known variations to some of these forms, they usually take the form of additional, smaller holes. In many cases anchors can be made of either a naturally shaped stone, or a worked block.


Stone fishing weight.

Types of stone anchor

No hole

A stone anchor without a hole drilled though it. It may have a groove cut around it (waisted). Stones of this type were sometimes used to weigh down a wooden anchor. Small versions were used as fishing weights and larger versions as buoy weights. Worked rectangular and rounded versions are known, as well as those based on an un-worked stone.

Stone anchor with groove for anchor line.

One hole

A stone anchor with a single hole though it. Also sometimes used to weigh down a wooden anchor. Smaller versions (maximum length 30 cm, weight less than 10 kg) are used as net-weights and very small examples (maximum length 12 cm, weight less than 500 g) as line-weights (dimensions taken from British examples).

Central hole

They can be found with a central hole these are sometimes called ‘ring anchors’. Quern and mill-stones can be recycled as anchors of this type. In eighteenth century Yorkshire, worn out mill stones were used as buoy anchors.

Variations are known with smaller holes at the edge, either to attach the stone to a wooden anchor, or for a smaller rope to help in handling the anchor

Stone anchor with a single, central hole.

Hole at end

Single hole anchors are also found with a hole at one end: these are the earliest known forms of stone anchor, examples have been found in the eastern Mediterranean dated to the second millennium B.C. These have continued in use until the present day, and are one of the most common type of fishing weight. Variations are known with an additional hole drilled into the top of the stone, linking with the main hole. This is believed to have been for securing additional ropes to aid recovery and prevent loss.

Drawing of an triangular stone anchor with a hole offset towards the apex.

Two holes

This type of anchor has two holes, one at each end of the stone. These anchors could be used in two ways, both of which are known from recent ethnographic examples. In the first example, one hole took a rope, the other an arm - usually of wood. In the second, only recorded on fishing gear, both holes took ropes. Wear-patterns on the stone should make it possible to distinguish which method was used.

Stone anchor with two holes.


This anchor was commonly used in the Mediterranean by both Greek and Roman shipping, though plenty of examples are know from the Atlantic, Red Sea and Indian Ocean. It is often referred to as a ‘classical’ or ‘Roman’ anchor, although evidence suggests that it continued in use for many centuries after the end of the Roman Empire. The holes form a triangle. The upper hole, which took the rope, can either be in the same plane as the lower holes or it can run across the stone. There are usually two lower holes (though three are known), always in the same plane. Rough examples, on flat slabs of stone, are probably ‘sand anchors’ designed to lie flat on a sandy seabed to achieve maximum grip.

Classical pattern anchor (Mediterranean).

Indian Ocean

This type is currently known from the Indian Ocean and Red Sea. It consists of a long stone block with the holes for the arms cut at 90o to one another.

It is known to have been used during the medieval period, though when it was developed is unknown.

Stone anchor with three holes, typical of the Red Sea and Indian Ocean.