Sunday, August 12, 2012

8/12/12 Report - Crusty Coins and Black Sand

Written by the Treasureguide for the exclusive use of

Surface Find Indicating Possible Presence of Other Targets
I often remind detectorists to keep their eyes open.  A surface coin might be the first indication you get of the possible presence of a nearby coin line or coin hole.  As I've mentioned before, I've known people who do not own a detector but have collected a lot of coins by walking the water line in the morning.

Coin lines and coin holes, being concentrations of coins recently deposited on or uncovered on the beach, often will leave a few coins on the surface.  Since you can scan a lot more area visually than with a detector coil of any size, visually scanning can often reveal signs that will tell you where to spend your time detecting.  If you suspect the possible presence of a coin line or coin hole, you might just quickly walk the beach to see if there is anything to tell you if there are any good spots to check with your detector.

I've talked about coin lines and coin holes in the past.  If you haven't been reading this blog and missed that, use the search box and enter the search terms coin line or coin hole.

The above photo shows one of two surface coins that I saw the other day, and they did point me to a hot spot.  What you are looking for are not coins that are on the surface because they were just dropped there, but coins that have been on the beach for a while, but recently deposited or uncovered at one location.

The coin shown in the photo was not a recent drop.  I could tell that from its condition.  It was partly encrusted with a green crust.

Here (photo below) are some of the coins in the coin hole that were not on the surface, but dug in the same area.

Notice the black sand in the above photo also.  You will generally want to check areas showing black sand.

Encrusted Coins
A lot of detectorists have trouble detecting in black sand.   I've not found it difficult at all.   Switch to all metals or pinpoint mode.  You will hear the black sand, but that is no problem.  You can learn to distinguish the difference between the sound of black sand and a target,.  The most difficult part is when the black sand is disrupted by a dug hole, foot print or something else that causes a sharp break in the layer of black sand.

You will find that if you dig a hole through a layer of black sand, you will get a target-like signal at  the edge of the hole.

There are times when discrimination mode will work better when detecting over a thin layer of black sand, but I usually prefer to stay in pinpoint or all-metals mode.

When detecting in black sand, sweep with the layer of black sand.   Generally that is more north to south.   If you sweep across strips of black sand, you will get more noise.

I generally DO NOT try to discriminate out the black sand, DO NOT reduce my sensitivity setting, or ground balance my detector to black sand.  I like to hear what is going on under the coil.  I don't mind hearing noise from black sand or other similar sources, but learn to mentally tell the difference between the different sources and sounds.   You can learn to pick out target sounds in a background of noise. 

Notice the heavy crusts on the coins.   Notice the black crust and shells on the top one.  That can provide important information about how long the coins were on the beach and where they came from.  That can tell you where to go next and where to look in the future.  Match the crust with the types of sand and materials that you find around the beach.   You might have to dig some holes to find the source material.

The black coin in the photo had a slightly different history than the others and came from a nearby but different area of the beach.

There aren't any real threats in the Atlantic right now.  Just two areas that have less than a 10% chance of forming into a cyclone in the next 48 hours.  One of those is over by Africa.

The wind is from the southwest and the seas running around one or two feet.   That means no improvement in detecting conditions.

Low tide this evening will be around 11:45.

Happy hunting,