Thursday, May 13, 2010
5/13/2010 Report - Testing Gold & Notch Discrimination
Touchstone Showing the Results of Two Tests.
I'll discuss this more below.
For a few months I've been talking about silver as a possible investment for those who want a precious metals investment other than gold. Silver is close to $20 per ounce now. Not a bad percentage increase.
Gold is now well over $1200 an ounce. Like I was saying over a year ago, I would hold onto my gold and silver finds unless I really needed the cash in a hurry.
Yesterday I showed a gold medallion. Some time ago I posted a link to a web site presenting an academic paper discussing the fact that gold does sometimes corrode, mostly because of alloys or other impurities in gold.
The medallion didn't have any markings on it and the material adhering to the surface made me wonder if it was really gold and if so, what purity.
One thing I would recommend to anyone that does a lot of detecting is to get a precious metals test kit. The cheapest would be an acid test kit. Electronic testers are nice but more expensive.
I know that most modern jewelry is usually marked, but sometimes it is faked and sometimes you find things that are not marked, especially older pieces. It is nice to be able to test your metals yourself.
You can get an acid test kit with a variety of acids for testing gold and other metals. My acid test kit has acid to test for 10, 14, and 18 karat gold as well as silver and platinum.
The photo that I showed at the top of the post shows a touchstone with two drops of acid on it. The drop closer to the top is 14 karat test acid. An edge of the gold medallion that was shown yesterday was rubbed firmly on the black touchstone leaving a trace of the gold. The 14 karat test acid was then applied to the rubbing. The rubbing of gold disappeared from the touchstone. That means that the material was either not gold, or if gold, less than 14 karat gold.
Another rubbing was made and the 10 karat test acid was applied (The lower of the two drops seen on the touchstone is the 10 kt acid.). You can see that the 10 karat test acid did not cause the trace of gold from the rubbing to disappear. That means that the material was at least 10 karat gold, but as we found out before, less than 14 karat gold. Further testing could if desired.
For intermediate karat values, you can use gold samples of various karat values and compare how the unknown sample compares to how the known sample reacts to the acid.
I can't give an entire lesson on using test acid here, but there are also ways to identify gold-filled and gold-plated items.
The silver and platinum test acids work pretty much the same way as the gold test acids, except the silver test acid causes silver rubbings to turn red.
The US debt, the threat of inflation and other threats to the US economy makes precious metals look like a very good investment even at current high prices.
A day or two ago I mentioned an old detector that has notch discrimination. As you probably know, I often discourage using any discrimination, but there may be times when you are working very junky dry ground, when you could use notch discrimination to sift through the junk. If you have the patience to pick up a lot of junk, you can often find goodies that have been hidden and missed by those using discrimination in junky areas. The next best thing to no discrimination is notch discrimination, which allows setting your detector to discriminate only a very specific type of item. You could set your notch settings to discriminate pull tabs for example, or nails, or bobby pins. Notch discrimination settings can be very precise and specific.
Usually a junky area will have one very predominate type of junk. It might be nails, pull tabs, bottle caps, or foil. Well, you can use notch discrimination to discriminate out the predominate type of junk and miss very little else.
My old machine has notch accept as well as notch reject. That means that if you are hunting a very specific target, you can select settings so that you will only find that type of item. Maybe someone wanted you to find an item they lost and that is all you are interested in finding and you want to find it as quickly as possible. You could use notch accept to discriminate out all other targets while hunting that one particular item.
Although I strongly discourage using any discrimination in most situations, there may be times when you might choose to use notch discrimination.
Select the detector that best suits the situation. It is often good to have a variety of detectors and use the one that best matches the situation. I often also recommend covering very promising areas with multiple detectors.
Different detectors have different strengths and weaknesses. By using different types of detectors to cover the same area, you will make sure that you didn't miss too much.
I just ran article on some of the history that is being preserved around DuBois Park. Here is the link.
Forecast and Conditions. The wind is still from the southeast. I'd be checking any of the spots that have been producing anything lately. I don't think anything will improve much for the next few days. Overall, conditions for finding old shipwreck coins on the Treasure Coast remain poor.
If anyone would like to get a good deal on some good furniture, I am helping an elderly lady get rid of some furniture that she can't use. The items are in great shape and you can get some good stuff cheap.
Here are some of the things she has for sale. Let me know if you have questions. the furniture is in the Port St. Lucie/ Fort Pierce area. You'll seldom be able to find stuff this good at these prices. Not all items are shown.