Showing posts with label sampling. Show all posts
Showing posts with label sampling. Show all posts

Friday, June 26, 2020

6/26/20 Report - Incorrectly Marked Gold. If You Dont' Know Where You Want To Detect Do Some Sampling.


Written by the TreasureGuide for the exclusive use of treasurebeachesreport.blogspot.com.

Gold Ring Find
Find and photo by Duane C.


Duane and I'd like to hear your opinions regarding the question he submitted below.


Unusual find beach detecting. A orange colored gold ring comes out ringing higher on my Nox than a typical 14k of its size. Higher numbers usually associated with higher carat like many 18k bands found prior. The color also closer to 18k than 14k. Originally believed it was 18k until I saw the marks inside. Surprised to see 14k not 18k. Tested at home with acid and electronic tester positive for 18K. The carat mark appears to be engraved not stamped. First one I’ve found like this. Makers mark maybe Cupillard but cannot find any further information on that maker. Ring appears no be marked wrong, odd one.

Mark on Same Ring Found by Duane.
Photo by Duane.


So what do you think about the item testing 18k with an electronic tester and acid test?

Send me your ideas.


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One of the most useful things you can do is sample various areas of the beach.  But sampling is a skill and must be done well to get the anything out of it.

You can't cover every inch of a beach.  There is just too much of it.  And you don't always know what some areas might be holding, so one good thing to do is take a sample.

Before I get into the details of how to do that, it will help to get some background information.  Unlike beaches, we know a lot about the distribution of IQs.   If you test a bunch of people, the average IQ should be around 100.  But if you test any single person, they will fall somewhere in a range between zero and something close to 200.  Fifty percent of the population has an IQ score between 90 and 110, and 95% fall between 70 and 130.  For IQ, we know what the distribution looks like.  It looks like the bell-shaped normal curve shown below.  The vertical access is the IQ score, increasing left to right.  So the most people have the average score of 100.




Source: Wikipedia.
If we were to flip a coin numerous times, we also know what that distribution would eventually look like (assuming a fair coin).  It would be binary distribution, like the one shown below.  If you only flip a the coin a few times you might get something like five heads and only one tail, but as you increase your sample size, eventually you'll get about the same number of heads as tails.



The point of that is, when you take a sample, when your sample is small, it may not reflect the overall population, so you have to take a larger sample to get a better sample of the total population, or in the case of metal detecting, the area.

When you are on the beach, you may not have a good idea of the distribution of good targets.  You might not know if there are any good targets at all within range of your metal detector, but as you do more sampling you'll get a better idea of what might be there.  You'll never know if your sample was sufficient.  One missed target can be a big deal.

I always remember several seasons ago when on Gold Rush TV show, Parker was thinking about mining a piece of ground and I wanted to shout at the TV, "Take some samples."   Eventually he got Tony Beets to do drill some samples, and I was so relieved.

On Bering Sea Gold you'll often see them panning a few samples.  Sampling makes a lot of sense when you do know how much, if anything, is there.  Rather than spending tons of time before you have any evidence of what might be there, why not do a little sampling.  If there is something there, sampling can also help you figure out how it might be distributed.

You can use your past experience and present goals to help you narrow down the area or areas you are interested in sampling.  You'll often be interested in some areas but not others.  Samples should be representative of the area  you are interested in.  You might want to sample multiple areas.  Some may look productive and others not.

With a metal detector it isn't like taking core samples.  You would scan an area with your metal detector using any of a variety of patterns.  One of the patterns I've discussed in the past is a zig-zag pattern, for example.  That pattern will allow you to scan sample high and low areas of a long narrow zone.

Samples must be representative.  That means the area sampled must be a fair unbiased sample of the area to which you want to generalize.  If you start by taking a small sample and get some evidence that the area might be worthwhile, you can then take a larger sample.  Sampling is a skill, which I can't discuss in great detail now.

To use an example we are now all unfortunately very aware of, we keep hearing about the number of COVID cases.  If you wanted to estimate the incidence of infections in the US you would make sure to have a fair random sample.  If, on the other hand, you are primarily testing those who seek testing because they have symptoms or have been in contact with someone who was infected or something like that,  that sample would be expected to have a higher incidence of infections than the general population - unless, unless of course there were also a lot of hypochondriacs in the sample. :)  Please don't make me spend about another 50 pages on that topic.  I'm actually trying to avoid it.

The quality of a sample is important, but so is the sample size.   A very small sample will have limited value.  There is usually a sample size that is large enough that if you repeat the sample you will get very similar results and below which, the results will vary wildly.

Think of the heads/tails coins experiment.  If you flip a coin three or four times, you might easily get all heads or all tails, but as you increase the number of observations your distribution will more closely resemble the distribution that you would expect, which is half heads and half tails.  You don't need thousands or even hundreds of flips to be pretty sure your sample distribution comes close to the expected 50/50 distribution.  But that much simpler example than most real-world problems.

A sample has to be representative, which means it has to reflect the characteristics of the area you want to know more about.  You can't just sample the wet sand or dry sand if you want to draw conclusions about the entire beach.  As you know, there are places that coins and other objects are much more likely to be found than others, whether you are talking about wet or dry sand.

I'll wind it up here for today.  Maybe return to the topic some other time now that a lot of the background has been laid.

Anyhow, if you don't know where you want to spend your time, you might consider sampling an area or multiple areas of the beach to see if there is any evidence that you should detect that area more thoroughly.

When you look at a beach and see several spots you might consider and don't have time to thoroughly detect them all, you might sample each one before deciding where to spend your time.

I know I didn't do a good job on this topic.  It would probably take a fifty pages to do that.  Anyhow, maybe I gave you something to think about.

I'll undoubtedly come back and try to clean this up.

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The surf is still small on the Treasure Coast and there is no tropical weather in the Atlantic on the National Hurricane Map.

Wednesday, December 20, 2017

12/20/17 Report - Hoard of Silver and Gold Coins Found. Basic Stages of a Systematic Hunt. Recognizing Various Types of Treasure.



Written by the TreasureGuide for the exclusive use of treasurebeachesreport.blogspot.com.


Hoard of Gold and Silver Coins Uncovered by Archaeologists.
Source: See Sci-News link below.

A hoard of 21 Islamic gold dinars, 2,200 silver coins, and gold artifacts dating to the 12th century CE has been unearthed by archaeologists digging at the Abbey of Cluny, a former Benedictine monastery in Cluny, SaĆ“ne-et-Loire, France...


Source: See link below.

Here is the link for more about that.

http://www.sci-news.com/archaeology/cluny-abbey-hoard-05433.html

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I recently saw an episode of the Oak Island TV program in which they used an ROV to explore one of the submerged pits.  Finally!  That is one of the things I was amazed that they didn't do long ago.  I

It also seems like the equally long overdue systematic drilling has pinpointed the area that they refer to as "the real money pit."   That will help them focus their efforts better.

I don't remember if it was the same episode, but I cringed as a mattock was used to retrieve a detected target.  That reminded me of several instances of beautiful artifacts being damaged or destroyed by careless recovery techniques.

I haven't talked much about search strategies lately.  I talked about that kind of thing more in the past, and I don't like to repeat too much.  As a result I probably don't repeat enough.  People probably don't remember what I said some years ago anyhow.

My first step is always research.  After that is visual analysis.  There are too many beaches and the beaches are too big to cover completely.  You have to be selective, and it is best to select on the basis of reason and data.  To spend your time well, whether you are on a beach or not, you always need to know something about what you are going after, the area, and the signs or clues that will help you narrow down your search.

After your research and scanning the area visually, the third thing is to do some sampling.  After you eliminate some areas and identify others as more promising, it is time to verify your visual observation by doing some systematic sampling.

Some people grid an area before they test it. That is fine, but I usually want to collect some data by checking an area out a little with my detector before deciding to spend that kind of time.  Analysis of  finds made during sampling, both good and junk finds, can tell you a lot, and it might not take very long at all to gather that additional information.

There is a lot that could be said about sampling including search patterns and analysis of finds, but that is not my intent now.  During sampling you will also more closely inspect the area visually and with your other senses.  You'll see the type of sand and other small objects such as shells or pot shards as you check the area with your detector, as well as feel how compact or lose the sand is, for example.  You might then choose to switch search patterns and/or detectors.

I've also described multi-stage searches in which the surface targets or junk targets might be removed first and then the search strategy refined as the same area is covered more thoroughly in stages.

The same basic process can be used on either beach or inland hunts, large scale project or jut a trip to the beach.   I always prefer a thorough systematic process even though a quicker scan and analysis can be the first step.

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That toy shown above sold for over $85,000.  I tell you that to remind you that treasure comes in many forms and it is good to be aware of the significance and value of many types of treasure.

People polish crotal bells like the find I showed yesterday and put a nice red ribbon on them and sell them for a good price.  The Polar Express movie made bells like that very popular.  You can get brand new ones or nice vintage bells.

Here is the source link for the picture above.

http://bangordailynews.com/2011/07/01/living/fine%C2%A0cast-iron-toys-can-bring-top-dollar/

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I haven't been saying much about beach conditions lately.  There hasn't been much change.

It looks like we might get some bigger surf after Christmas.  That is what the MagicSeaWeed web site is showing.  I'll keep watching that.

Happy hunting,
TreasureGuide@comcast.net


Thursday, November 23, 2017

11/23/17 - Another Kind of Treasure Coast Treasure: Fossils. Easter Island Stones. Sampling. Happy Thanksgiving!



Written by the TreasureGuide for the exclusive use of treasurebeachesreport.blogspot.com.

Vintage Post Card OriginallyReceived by My Grandfather in 1909.

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Did you notice that this Megalodon tooth fossil received a winning bid of $550 in the recently concluded Sedwick treasure auction?

Auction Listing From Sedwick Auction 22


I showed that to remind you that there are other types of treasure on the Treasure Coast besides coins and artifacts.  You can find fossils all the way along the Treasure Coast.  I've seen fossils on most of the beaches.  Some beaches provide more fossils than others, of course, but you can find fossil shark teeth, as well as rhinoceros, giant sloth, camel and even mastodon bones on the Treasure Coast.

This meg tooth is more valuable than the vast majority of what you might find, but there are valuable fossils to find, and if you like finding old stuff, you should know that Treasure Coast fossils can be millions of years old.

Below are a couple of fossils I picked up the last time I was at the beach.  Beach conditions were not good for finding fossils, but I noticed them along the way.  They aren't really worth anything, but it shows that fossils are out there.

Matrix Containing a Few Pieces of Fossil Bone.
On the left bottom of the photo above is a vertebra.  At the top is larger piece of fossil that I have not yet identified.

Larger Piece of Broken Fossil Bone.
This one is larger and a little unusual because of the two colors.

Keep your eyes open.  You never know when you might see a nice shark tooth or something else nice.

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There is always more than meets the eye.  You've seen the huge stone heads of Easter island. but they are actually more than heads.  They have bodies too.  The bodies were buried over a period of about 500 years by natural processes. They didn't sink - at least not much.  They sit on rock foundations where they were originally carved and then raised from horizontal to vertical.

Here is the link.

https://www.forbes.com/sites/trevornace/2017/07/26/famous-easter-island-heads-have-hidden-bodies/#220cb45af804

People wonder how huge stone blocks like these could have been moved.  In this case they weren't moved - at least not far.  They were carved on location and then flipped up.

Use your head and save your back.

Speaking of which, I was glad to see on a recent episode of Oak Island that the fellows FINALLY decided to do things a bit more systematically and methodically.   They finally drilled a grid of holes to do some testing and sampling.  I've been screaming at the TV for them to do that for at least a couple of years.  I felt the same way when the Hoffman's ( I think) finally had Tony Beets (sp) do some serious core sampling.

In the past I've done a few posts on sampling.  Sampling can save a lot of time.  Very important concept.

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Here is a sad article.

http://www.foxnews.com/us/2017/11/18/wwii-veteran-calls-for-help-and-dies-as-nurses-laugh-video-shows.html

While you are being thankful, express your gratitude by being kind, especially to those who need it most.

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Today we'll have a three to five foot surf.  The next few days the surf will be decreasing.

Happy hunting,
TreasureGuide@comcast.net

Monday, July 24, 2017

7/24/17 Report - Type 5 1714 Mexico Escudo: More Details. Assay and Sampling of Precious Metals Reference. Get Smart.


Written by the TreasureGuide for the exclusive use of treasurebeachesreport.blogspot.com.

1714 Mexico Escudo.
Photo submitted by Captain Jonah Martinez.
If you've been following my posts, I first thought the the 2 escudo recently found by Grant of the Capitana was a 1714.  Then I noticed the two fleur de lis in the panel at the 4 or 5 o'clock position. The design shown in the Bowers and Ruddy catalog for 1715 coins showed two fleur de lis in that panel at the 4 or 5 o'clock position, but only one of the varieties for the 1714 Mexico escudos in the Bowers and Ruddy catalog showed two in the same location, I concluded that Grant's escudo might be a 1715 escudo.  There is also, however a 1714 variety that has two fleur de lis at that location, (See illustration below.) like the escudo shown above.

Type 5 1714 Mexico Escudo
Source: 1977 Bowers and Ruddy Auction Catalog

As you can see in the illustration, there are only two fleur de lis in the panel I've been discussing for the 1714 Mexico escudo (red arrow).  That differs from the variety I showed yesterday for the 1714, which had three at that part of the shield.

Captain Jonah sent me the photo of a clearly dated 1714 Mexico escudo (top of post) that shows two fleur de lis in the same field.  That escudo is similar but not exactly like the type five shown in the illustration.  There is no "o" above the "M" mint mark (blue arrow) on the type 5 illustration, but there is an "o" above the "M" on Jonah's coin..

 I can't see any other features that would in my mind definitely distinguish between the two dates.  Maybe someone else can.

Like I said many times before, I'm not an expert in numismatics, just an interested student.  I learned a little more by muddling around with this.  Hope you did too.

Thanks to Captain Jonah for sending such a great photo for study.

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While doing some research on one of my longer standing mystery items, a 10 gram silver ingot or whatever, I found a great reference book.  The book is The Sampling and Assay of the Precious Metals, by Ernest Smith, published 1913.  Click on the title if you want to take a look at the free ebook.

What I've read in that book makes me think that the 10 gram silver ingot or button probably has something to do with the assay process.

Below is a brief excerpt from the book just to give you the idea.



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Teresa T. sent in a link to a supplement that seems to be endorsed by famous people such as Stephen Hawking that is supposed to dramatically increase mental alertness and IQ.  I'm too old to get smart now, but here is the link.


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I've been watching a fellow do some involved work and having a lot of trouble with it primarily due to poor planning and preparation.  An ounce of prevention is worth a pound of cure.

You might consider detecting early or later to avoid the hot mid-day sun and afternoon thunder storms.

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We're still having a one to two foot surf on the Treasure Coast.  No change in sight.  The tides are big though.

There is no tropical activity of interest in the Atlantic or Gulf.

Happy hunting,
TreasureGuide@comcast.net





Friday, January 13, 2017

1/13/17 Report - Gold Cross Pendant Found. Site Analysis and Sampling: Brief Case Study.


Written by the TreasureGuide for the exclusive use of treasurebeachesreport.blogspot.com.

Find and photo by Duane C.
Written by the TreasureGuide for the exclusive use of treasurebeachesreport.blogspot.com.

Just yesterday I mentioned that I hadn't been posting much on modern jewelry lately.  Well, I just got the photo of this nice find.

Duane said, Found on east coast 18k lots of makers marks age unknown. 

Congratulations Duane.

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This isn't a story about a valuable find.  It is a story about site analysis and investigation.  The particular site showed signs of being "right."  By that I mean if anything was in the area the chances of finding something was good.  I could tell that the site was "right" by looking at it.  

The base of a cliff was eroded.  Below the cliff was hard sand slanting down to the water at a very slight angle.  Then the sand flattened out.

As I explained not long ago, a visual site analysis should be the first step.  That can tell you a lot about where to spend your time most efficiently.

When I walked by the area and noticed the washout, I recognized that it was an area that would probably reveal something.  After my attention was drawn to that area, it was just a few minutes before I noticed the bottle shown below.

It is a small bottle, embossed "WHITEHURST."  It originally contained a cough medicine.  The bottle is from the early 1900s.

I already knew something of the history of the area.  There could possibly be something there from almost any time period, but most human activity would have most likely been late 1800s and early 1900s.  The bottle was consistent with that.




So, the area looked right, and it revealed an older item in almost no time.  As is often the case, the first clue was glass or ceramic.   

The water was coming in and covering the area, but I didn't expect it to completely disappear, so I decided to return the next day to look it over a little more.

On my return visit I took a metal detector.  The area was covered with junk, both metal and non- metallic - some on the surface and some buried.  The detector was constantly giving signals.

I wasn't digging anything at first, just getting an idea of the situation.  Then I decided to dig a few - I think it was five or six, of the better signals.

Notice that so far, all I am really doing is sampling.  I am analysing the situation.  First visually, then with the detector.  I do not believe at this point that there is any reason to spend much time or effort on this site.

Part of my analysis is knowing something of the history of the area.  The people that lived in the area in the early 1900s were not wealthy at all, and worked in agriculture.  The site accumulated a lot of junk.  There is not reason to expect gold coins, good jewelry - only a small chance of finding a coin or two from the 1900s and a smaller chance of finding a coin from the 1800s

Knowing what went on at a site in the past can be a big help.  How many people were there and what were they doing?  This is not a fancy resort visited by many people over the centuries.  Just the opposite.  This site has a very small chance of revealing anything valuable, but there is some chance that something from the late 1800s or early 1900s might show up.  If I was trying to find something valuable and if this site wasn't very close to my home, I wouldn't bother with it at all.

There is almost no chance of finding something like the gold cross pendant at this site, so if that is what you are after, forget this site.  This is a relic hunter's site.

There is more chance that a pre-contact sight find would be made there.  A check-stamped shard was found not too far away.

Detecting in this area was very difficult because of all the junk.  Much of the area was also now covered with seaweed. 

After spending a  few minutes just scanning the area with the detector, I decided to dig some of the better signals - very few though.


Small Compact Dating To 1925

One of the things I dug was this Princess Pat compact, in surprisingly good condition.  The hinges still worked.  I opened it up and the broken mirror was still in it.  I was very surprised that it would still open.


It was easy to find out about Princess Pat.  This particular compact is the style that was sold in 1925. The date of the compact is very close to the date of the Whitehurst bottle.

My conclusion is that the compact was on the bank, where it was preserved - not in the water.

The compact is shown above.

So far I have spent about half an hour looking at that area and will investigate it more in the future since it is so convenient to me.  I wouldn't bother if I was serious about making a good find, but there is the slimmest possibility that something much older will show up, and maybe even something like an older coin.  The likelihood of either of those is small, but there could be some sort of interesting relic to be found.  

While these were no great finds, the case illustrates some of the steps and factors to consider in site analysis.

Here are a few.

1. Visual site inspection.  Determine if current conditions are good or not, and what spots might be most promising.
2. Consider history of the area and types of activity that took place at the site.
3. Sample with metal detector.
4. Evaluation of finds.  Age and whatever else they might tell you.
5. Consider future opportunities for additional searching.  Is immediate intensive search indicated or not?


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The surf is supposed to increase up to seven feet today.  Not bad, as far as size goes.

There will be big tides too, including a nice negative tide.

Happy hunting,
TreasureGuide@comcast.net

Tuesday, October 6, 2015

10/6/15 Report - 16th and 17th Century New World Shipbuilding. Sampling and Detecting Strategies.


Written by the TreasureGuide for the exclusive use of treasurebeachesreport.blogspot.com.


Some Artifacts At The Conservation Lab.
You have to make decisions.  Hopefully they are good strategic decisions based upon information.

One decision is which detector to use.  I'm not talking about which detector to buy, although that will determine what you have available to use.

As you probably know I talk about detectors as being something like gulf clubs.  Sometimes one will be the best choice and sometimes another will be the best choice.

Yesterday I was digging a lot of deep holes. It was tiring, but I had a reason for doing that.  I thought there might be some shipwreck spikes to be found, and  I wanted to know if there might be shipwreck material in the deeper layers of sand.

As it turned out I didn't find any spikes.  I did find some iron rods and things, but nothing definitive.

If I just wanted to quickly skim the coins I would have put away my driver and pulled out my putter. Of course sometimes coins are deeper, but most often when coins come out of erosion, they are not very deep.  In fact, they are most often in the first inch or two.

By digging big deep holes I got a good look at the deeper layers.  Under about a foot of sand there was a layer of modern junk along one stretch.  It got covered maybe back some years ago.

I often do some sampling and then make decisions based upon what I learn.  In some cases it takes longer to get a good sample than other times.  Once you get a good sample, you can then change strategies.

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A couple cargo ships went down in the Bahamas during Hurricane Joaquin.  It appears that lives might have been lost as well as the ships and cargo.  Don't forget that hurricanes cause a lot of problems.

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Below is a link to an interesting article on ship manufacture in the New World.

New Spain provided great lumber, but the iron had to be brought from Spain.  The large trees of South America actually allowed larger beams to be constructed from one tree rather than assembled as would be the case if the same ship was constructed in Europe.

Spanish Ships and Shipbuilding in the Atlantic Colonies, Sexteenth and Seventeenth Centuries, by Chuck Meide, Dec. 2002.

http://www.academia.edu/3258279/A_Plague_of_Ships_Spanish_Ships_and_Shipbuilding_in_the_Atlantic_Colonies_Sixteenth_and_Seventeenth_Centuries

When you go to this site it looks like you have to register to download it, but you can read it online without doing all of that.

Here are just a couple interesting excerpts.


That will give you some idea of the type of information you might find in this work.

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There was a shark bite at Pepper Park yesterday.  It was on the foot and in shallow water.  They closed the park, but it is probably open again.

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Happy hunting,
Treasureguide@comcast.net