How to pinpoint and recover a metal detector target

Start in normal search mode

Do not press pinpoint as soon as a tone appears. First sweep the target with the normal motion mode and decide whether the response is repeatable. Shorten the sweep, approach from two directions and listen for a consistent centre. A broad smeared response may be a large shallow object rather than a coin.

Lift the coil several centimetres and sweep again. If the target remains loud across a wide area, expect a can, sheet metal or multiple objects. This size check reduces unnecessary turf cuts and helps choose a safe recovery point.

Use the cross-sweep method

Pass the centre line of the coil over the response from left to right, then mark where the strongest point occurs. Turn roughly 90 degrees and repeat. The intersection gives a useful first estimate.

With a Double-D coil, the strongest search strip usually runs along the centre spine. Wiggle the coil in short movements over the target and pull it slowly backwards; the response often drops as the target passes the front centre edge. Coil design varies, so test this method over visible objects with your own machine.

Use the detector's pinpoint mode

Move the coil away from the target, activate pinpoint mode as the manual instructs, then sweep slowly across the estimated centre. Many detectors use a non-motion audio response that becomes stronger as the coil centres over the object. Some displays also narrow the position or show depth.

Avoid activating pinpoint directly above the target because the detector may detune around it and produce a small or offset response. If the audio seems broad, release the control, move away and start again. Retuning closer to the target can narrow the response, but over-retuning may hide it.

Depth readings are estimates

Most detector depth indicators assume a coin-sized target in a typical orientation. A large deep object can appear shallower; a small or edge-on object can appear deeper. Mineralised ground, coil choice and sweep height also change the estimate.

Use depth to plan the recovery, not as a promise. If the signal continues below the depth agreed with the landowner, stop rather than expanding an unauthorised excavation.

Mark the centre without stabbing the target

Place a plastic marker or your boot toe beside the estimated centre. Do not drive a screwdriver or probe into the strongest point; that is where a coin or fragile object is most likely to be. Plan the first cut outside the target response.

On dry sand, a scoop can remove material without a turf plug. On pasture, the surface and permission may allow a hinged plug. Parks, sports turf, pasture, ploughsoil and foreshore each need different recovery methods.

Cut the smallest recoverable plug

Only cut turf when permission and conditions allow. Use a clean curved or horseshoe cut that leaves one side attached where practical, keeping roots connected. Lift the turf gently and place loose soil on a cloth or kneeling pad.

Do not make a tiny plug that tears apart. A slightly wider controlled hinge can reinstate better than a narrow cone. Avoid recovery in saturated, frozen or drought-stressed turf because the surface may not heal cleanly.

Retune the handheld pinpointer

Switch the pinpointer on away from the detector coil and metal tools. If it chatters in mineralised soil or salt, retune it close to the ground according to the manual. Start on a stable sensitivity rather than maximum range.

Scan the surface of the plug, the hole walls and the removed soil in a fixed sequence. Audio or vibration that intensifies toward the target is more useful than random movement. Keep the probe parallel to a wall when checking it, then rotate to narrow the strongest point.

The Garrett PRO-Pointer AT provides proportional audio and vibration, three sensitivity levels and a fast retune function. Its 360-degree detection area is useful in a hole, but the tip and sides still need a methodical scan.

Keep the main detector and pinpointer apart

An active pinpointer can interfere with the main detector, and a nearby coil can affect the probe. Place the detector far enough away that the pinpointer remains stable. Do not rest a spade, phone or finds pouch against the hole while testing.

If the pinpointer sounds everywhere, reduce sensitivity or retune. If it remains silent, recheck the target with the main coil before digging deeper. The object may be in the plug, on the spoil cloth or displaced to one side.

Recover from the side

Once the pinpointer identifies a small area, loosen soil beside the response with fingers or a suitable non-scratching tool. Do not pry directly against a coin edge. Lift the object with supporting soil when it appears fragile, wet or corroded.

Photograph an unusual object before rubbing off soil. If several objects appear together, a container or compact layer is visible, or the signal extends below the permitted depth, stop and follow the record-a-find process.

Solve common pinpointing errors

The target seems to move

Check for two nearby objects, a nail producing an elongated response or loose metal in the spoil. Return to normal search mode and sweep each direction with a shorter arc.

The pinpointer sounds around the whole hole

Retune against the soil and lower sensitivity. Highly mineralised or salty ground can reduce useful range. Make sure the probe is not responding to the spade, detector coil or a metal kneeling aid.

The target disappears

Scan the plug, cloth and boots, then pass handfuls of loose soil below the stationary coil or beside the pinpointer. A small object may stick to muddy gloves or sit edge-on in a plug.

The centre is beside the detector mark

Deep targets, sloping ground, target angle and coil geometry can offset the apparent centre. Crossing from two directions and checking hole walls is more reliable than trusting one pass.

Recheck and reinstate

Sweep the recovered object away from the hole to confirm it caused the signal. Then recheck the hole and plug for a second target without automatically widening the recovery. Multiple objects close together can be archaeologically important.

Return loose soil, close the turf hinge, press the plug level and lift flattened grass. Remove sharp modern debris. From standing height, the recovery should not create a trip edge, hollow or visible scatter.

Good pinpointing is measured by the ground left behind, not by how quickly the object reaches the pouch.