Greetings. I just acquired this sacred coin of Jesus. Could you please assist me to learn how to clean it safely and properly, and to preserve it as well . Thanks a lot. Charles
First off, soak it in distilled water, changing the water every few days, and brushing the coin very lightly with a soft toothbrush. That might get enough of the dirt off to satisfy you, without taking more drastic measures.
I would not recommend cleaning it. Do you think that currators in museums clean the artifacts they receive before putting them on display? no of course not. Why? because it affects the metal of the object and makes it shine unnaturally which will lead people to question its authenticity. I was recently at the Franklin Institute and they have a pompeii exhibit going on and halfway through the exhibit there was a display of coins found from a slave that almost made it out alive. Anyways the coins were not cleaned and looked pretty similar to your coin.
Not sure why "sacred", its an anonymous Byzantine bronze. I own the complete set, (except for a couple of later ones which I am not really sure belong). John is right, distilled water and brushing every couple of days until its at a point you like. Having cleaned coins like it, I will say its best to stop when the contrast is pleasant and not clean all of the dirt off. It will be much more attractive when you remove half the dirt than if you remove all of it. I can tell the patina is not a terribly attractive one, so you are better off with a "sandy patina". As an aside, these are really interesting since each ruler chose his favorite portrait of Christ from a famous church. Almost all of the originals are now lost, so the only way we know what these famous paintings look like are from these depictions on anonymous bronzes.
Josh, almost all ancient coins have been cleaned to some degree. Cleaning is just as accepted among collectors of ancients as it's reviled among collectors of moderns. And, yes, many of the artifacts you see in museums have been cleaned - some very lightly, others more thoroughly. I'm not sure where you got the idea that artifacts don't get cleaned.
Most ancient collectors clean coins. Many need to be conserved properly. This is why we freely share the best ways to do so without risking damaging the coin. Personally I have cleaned hundreds, but know of others that have cleaned tens of thousands. Almost all coins found in hoards have been cleaned. If its not gold, it simply will not come out of the ground after 1000-2000 years without needing to be conserved.
Not every artifact is cleaned but I will agree that some definately are. I am just against cleaning anything of historical value. This holds true especially with antique guns. you do not want to clean them because it destroys the value. But hey if you want to clean your coins to make them more presentable go right ahead. Afterall it is your coin I personally would not clean them.
It gets back to the old adage "don't clean coins". Its a good adage because all new collectors ruin coins by "cleaning" them. So, its helpful just to put a blanket statement out there. However, I have been collecting coins for well over 30 years sir. I have cleaned US coins successfully, and know how to do it properly without destroying value. So the rule is not absolute, even with modern coins. With ancients, however, there has never been such a rule. If you were an ancient collector you would know that proper conservation and custody is one of the things we must do with these coins. Ancient coins can develop bronze desease, have encrustations that will further damage the coin if not removed, and simply have centuries upon centuries of dirt on them. Therefor, we, as a group, learn how to properly conserve and protect our coins to be able to pass them along to the next generation. We are pretty good at it, as evidenced by the millions of ancients that have been passed down through the last centuries from collector to collector. So, no one should ever clean a coin if they do not know how to do so properly. But, if a coin needs conserved, then its the duty of the collector to learn to do it properly and save the coin. I have saved hundreds of US coins as well from corrosion by dipping coins that were too corroded. If I hadn't have done anything, those coins would forever be severely damaged.
Actually...many museums do clean the coins in their collections. I have viewed coins in museums all over the world and this is a common thing. Museum curators are not coin collectors and do not subscribe to the same rules that collectors do.
The Museum of Fine Arts in Boston has a decent sized collection of ancient Greek and Roman coins. Every one of them is bright and shiny. Its kind of scary seeing an entire collection like that over cleaned.
They may not necessarily be over-cleaned. Gold is mostly inert, so it doesn't tarnish like silver. If you clean it even mildly, it's going to look shiny and new. Most silver ancients come out of hoards encrusted with some amount of dirt, but the dirt cleans off easily, also leaving a shiny coin. Bronze is the complicated metal, as it acquires a patina over the centuries, and sometimes gets encrusted with mineral deposits. The key to preserving a bronze coin is to eliminate the dirt and perhaps some of the deposits without stripping the patina. To that effect, distilled water, a soft brush, and a toothpick are going to be your best first tools.
http://blog.britishmuseum.org/tag/coins/ https://www.britishmuseum.org/explore/highlights/article_index/c/conservation_of_silver_coins.aspx I should probably add some context. The British Museum probably has one of the largest ancient coin collections in the world and the majority of the coins will have been cleaned as will all hoard finds in Britain. Detectors report the hoard to the PAS who let the BM know who cleans a select number of coins to see if they are of incredibly important historical significance. If not, I believe in some cases, the coins are returned to the detector and if they are the detector is compensated. At least that is my understanding.
I know it's pedantic, but there is a difference between cleaned and conserved. Most would agree that cleaning is bad, but if you don't conserve objects they will deteriorate to the point of not being historically valuable. This goes for all antiques, guns included. If they are not properly stored and conserved they deteriorate and lose value too, the critical part is in doing it properly.
In my experience (degree in archaeology), cleaning refers to the basic removal of dirt and encrustation, whereas conservation refers to methods and materials used to ensure long-term survival of the object. There is certainly overlap between the two.
I agree. Its been common on this board sometimes to say proper cleaning is "conservation" and improper cleaning is "cleaning". I have never bought that, though, since me soaking an ancient in distilled water and brushing off some excess dirt is not "conserving" the coin. The coin would problably be best conserved by leaving the stable dirt on it, but I would not enjoy the coin. However, dipping an overtoned coin or digging out and treating a spot of bronze disease IS "conserving". So, it would be nice to say "proper cleaning" should be labeled "conservation" to differentiate it from the carnage of destroyed coins that is newbie "cleaning", but I do not think that is correct. The differentiation should be between "proper cleaning" and "newbie I do not know what I am doing so I am going to destroy a coin cleaning".
Hey, I know that the opinions will be mixed between this version and the OP coin ... but I still wanted to toss-in my version (which I personally have zero-clue how much "cleaning or conserving" has taken place?!!) ... I just like it!! Anonymous Folles, Basil II & Constantine VIII Æ26 (Class A3) Constantinople mint circa 1020-1028 Diameter: 26 mm Weight: 7.04 grams Obverse: Facing bust of Christ Pantokrator Reverse: Legend in four lines; ornament above and below Reference: DOC A2.40; SB 1818 Other: 6h … dark gray-brown and red-brown patina => oh sorry ... wow, I love your new coin (I admit that it still looks very cool with a bit o' grunge on it!! ... congrats on a sweet new pick-up)
I think dry cleaning would be better to the high points of the lettering and on the obverse. That may bring out the details better. I would not soak the coin in any type of liquid. The coin has a desert patina which should be preserved. You can dry clean a coin by using toothpicks and by using soft brushes, but I don't think I would brush this one, just use toothpicks and go in very small circular motions.
The OP coin reminds me of the Shroud of Torin. I'm with GG on this one. I don't think I would clean it over much.
I will guarantee you Steve your coin was cleaned up after it came out of the ground. Have you ever seen copper ancients coming out of the ground? Even if they were buried in pots they have loads of encrustations on them. This happens so frequently and commonly to the coin before they ever reach collectors we do not think about it much.