Re: [African_Arts] Rust vs Patina
- Hi Michael,This is an area that I know nothing about because I rarely collect objects made of metal from Africa, but there is information out there that can be of help to you.We have had some discussions in this group regarding care and maintenance of wooden African objects and I have archives of conversations about the maintenance of metal African objects.Normally care and consideration should be given when attempting to clean any object, and my rule of thumb is that I usually leave an object alone aside from dusting it unless there is clearly something on the object that was not meant to be there.In my opinion, surface rust is something that probably can and should be removed from a piece because I think that it distracts from the piece. I don't think by removing it you will effect the value in a negative way, but you will certainly effect the aesthetic value of the object in a positive way.The information below should be of help to you.RANDThe following bit of information is from Dr Peter Westerdijk who is known as an expert in the field of African weapons and the like.The information, and additional examples, can be seen on the site of David Norden on the following page: http://users.telenet.be/african-shop/weapon-maintenance.htmby Dr Peter Westerdijk
august 21, 2004
When African blades are rusty, or worse, pitted and partly eaten by corrosion, it is always a sign of neglect.
Africans in the old days were keen on keeping their weapons in good shape. Photographs dating back to colonial times show warriors with arms in top condition, brightly shining as the result of regular cleaning.
When we find rusted surfaces, either superficial rust or deeper corrosion, we can clean them by applying waterproof sandpaper of various grains, ranging from fine for light rust to more heavy grains for serious corrosion.
Always use a lot of water to keep your paper clean. A dripping tap gives you just the amount of running water you need for the job.Never work your surface too bright; just clean is enough.
As for copper and brass weapons or wire of the same materials applied to handles and sheaths, touch them as little as possible to maintain an old appearance. When cleaned, seal off the surface with an acid-free wax or a thin layer of weapon-oil and corrosion for your items will be a thing of the past.
Additional information by Jerry Jacob:
There are a couple of adjuncts to your treatise on rust removal and prevention. The nomenclature for the sandpaper to which Dr. Westerdijk refers is Wet/Dry and is available at most hardware stores or Auto Body Supply outlets. This is available in grits from very coarse (100) to ultra-fine (1000). Rather than use oil or tap water most professionals use a combination of water and dishwashing detergent or soap. Always start with the finest grit paper possible and work to even finer grits to avoid scratching. Use a light circular motion on heavy rust working to long circles with the finer papers... make sure to dip in the soap solution often. Don't try to sand out small spots it's better to leave them or work a larger area to feather the edges. The hydrophobic action of the soap helps keep the paper free of clogging and also acts as a lubricant making the job easier. A 1/1 mixture of Boiled Linseed Oil and Turpentine protects the cleaned metal better than any other product and is easily removed without damage to the object.
Additional websites and discussions on the Internet regarding the topic:
Michael <povertyrow@...> wrote:
My currency knife is made of iron with a fairly even layer of rust
over the iron blade. Handle is wood with some type of metal banding.
My question is about the rust. Some of the rust is just surface rust.
A gentle wipe with a soft archival paper reveals rust stains.
Now iron will rust, and rust easily. My question is: Is this surface
rust relevant to the piece? Would the piece be percieved as "damaged"
if the rust were removed? Should the iron blade be treated in any
way? Etc etc etc. Basically a question about how rusted iron should
be perceived and treated in this art.
I have made a composite scan (not the best but it gives you a feel)
of the knife in 3 sections (then joined them together). I think it
gives you a feel for the knife.
So bottom line? How does one care for something like this? Does one
remove the surface rust but leave the rust that has truly joined with
the iron? I would consider rust that has joined with the metal a
true "patina" but simple surface rust that can be wiped with a cloth
not to be patina.
As an aside, I also collect old paper (late 40's to mid 50's comic
books and 30's and 40's move posters) and have spent many years
studying paper restoration. Considerations such as the patina versus
surface rust, treatment and conservation of the metal, etc. basically
crossover into concepts of paper restoration (or at least get the
brain working into these area).
So how does one conserve such metal?