Friday, March 30, 2012
3/30/12 Report - To Clean or Not To Clean Finds
To clean or not to clean, that is the question for today.
Cob As Found.
I recently received an email asking if some found items should be cleaned or not.
That seems like an easy enough question, but it is actually a difficult question to answer. It depends upon a lot of factors. And some of it is personal preference. Some people like their finds to look like they were just made, and others like them to look like they did when they were found.
I've shown this cob before, but since I am talking about cleaning finds today, decided to show it again because it is a good example.
One thing that will determine if you should clean a find is the found condition. Some things will be in very nice condition when found, and others will be completely corroded or encrusted and completely unrecognizable.
Same Side of Same Cob After Cleaning
Corrosion is one thing you normally can't reverse. Sometimes a corroded item can be improved a bit by removing some of the corrosion or encrustation, but sometimes it will only get worse.
Encrustation can often be removed very effectively. And things can be very well preserved under the crust - depending in part upon the type of metal.
I've shown one good method for cleaning silver coins. Just take a look at Bill's silver coin cleaning lesson in my links list. Of course, it doesn't have to be a silver coin, it can be a silver artifact and the same procedure will work very nicely.
Bill's method is what was used on this cob.
It helps a lot to know what metal the object is of. I highly recommend an acid test kit and anything else that will help you positively determine what the metal is.
The first step is to study the object. Don't jump right into cleaning it. Not only is knowing the type of metal important, it also helps to have some idea what the object is, how valuable it is, and what condition it is in before starting.
Also your experience level is a big factor. Don't even think about cleaning something that might be valuable or that you really care about if you don't have some level of experience with the method of cleaning that should be used.
I had this cob for a couple of years before I finally decided to clean it. For one thing, my curiosity got the best of me. And I also got to the point where I was confident that I could do a good job of cleaning it.
I've found that all methods of cleaning coins or artifacts require frequent monitoring. Leaving something in a solution too long or continuing the process too long can sometimes cause irreversible damage.
Watch the process closely. Don't over do it.
Another alternative is to have your item professionally cleaned. Some of the museums and salvage operations will sometimes clean an item for a small fee. It might be worth checking into that option.
If the item is too encrusted to even know what it is, you can usually remove at least part of the crust if not all.
If the object is iron, it might have completely dissolved leaving only a mold of the original object. If you don't break the mold you can sometimes make a mold and create the original form of the object.
A light sand crust can be removed in a variety of ways. Sometimes by using a solution, and sometimes by using a dental pick and removing grains of sand one at a time.
A heavy crust can sometimes be cracked by using a vice or light tapping. This is a relatively dangerous process and should only be used when known to be a safe alternative.
Cleaning is a slightly different issue than conservation. Many objects will continue to deteriorate if they are not conserved. That is particularly true of iron. If it was submerged in salt water for a while, when removed it will eventually fall apart. It might look ok. You might not think that it is necessary to clean it, but it can fall apart.
Cleaning is often the first step in conservation, but conservation can be a more important issue than cleaning.
One web site that provides excellent information on conservation of iron, and virtually all other materials, is the Texas A&M University nautical archaeology web site.
Here is the link to the section on conserving iron objects.
Most shipwreck objects other than gold or silver should probably be conserved. Cleaning might be enough for silver, although a protective coating can be helpful.
Without trying to get into more detail and to sum things up. Deliberate long and hard before deciding if you are going to clean an object. Try your best to determine what the object is before proceeding. Study and make sure you experiment with the process that you plan to use on things you don't care about before trying it on something important. And closely watch the process as you proceed. Sometimes nothing is worse than over-cleaning. When it comes to cleaning objects, it is better to delay action than jump into something that you don't know enough about.
The bones of British soldiers dug up by archaeologists in 1950 were finally repatriated and buried.
Beach conditions remain poor. I did visit one beach that had a low flat front beach this morning and found a cheap ring.
Clustering is something I often talk about. It was very evident on that beach this morning. You could walk a good distance whithout a single signal and then run into a cluster of items.
The water looked really nice. Small swells were rolling in at long intervals. Find a dip and take a look.
Or, when sand bars are moving in as some of them will be now, if there have been a lot of swimmers on the bar, check the back (east side) of the bar.