Ask MetaFilter questions tagged with copper

I know I'm lucky my house didn't burn down, but do I really need to buy new cookware?

Meg_Murry — Mon, 20 Jul 2009 06:54:22 -0800

Can I safely use a burnt Revere Ware copper-bottomed saucepan? I have an old Revere Ware copper-bottomed saucepan, maybe 30 years old. I was heating some water on the gas stovetop and got distracted--called away to another room, stupidly left the pot boiling for a good hour or so. By the time I returned, all the water had boiled away, the inside of the pot was swirled with white powdery marks, and the bottom had a thin layer of black burnt stuff flaking off. Under the black layer, which I can scrub off pretty easily, there's still copper.

I'd rather throw away the pot than risk having the bottom fall off while cooking or some other disaster, but I don't want to throw away a still-usable pot. Is it safe to use?

What are these old copper printing plates?

gemmy — Sun, 10 May 2009 17:24:35 -0800

Anyone recognize these old copper printing plates? They were used to print some sort of encyclopedia or other information book, but which one? In the late 90s, my mom and I picked up some old copper printing plates [link goes to Flickr set] from an estate sale in Connecticut. We spent an hour or so picking out a few neat-looking ones from a huge set (I would estimate about 100-150) of these printing plates, stored in boxes and wrapped in old newspaper (the newspaper was from the 1950s, if I remember right). Each plate has a volume designation and a number. I did some serious looking in libraries and such at the time, but couldn't find anything about what these plates might have been used for. I have looked less seriously every few years since, but haven't found anything useful.

It looks like the copper plates were used for an encyclopedia type book, but the text from the plates isn't turning up anywhere online. For example, one of the plates says that Richard Wagner told Franz Liszt "Your God makes a lot of noise". But I can only find one place online that even mentions that Wagner quote, in a book from 1921. I only took photos of the ones I have hanging on my wall. I have two more plates in the closet - one is a picture and text about Tian Tan in Beijing, the other is a picture and text about the Great Wall of China.

I know it's a long shot, but do these plates look familiar to anyone? Any ideas what book they might have been used to print? Any suggestions for finding more information would also be appreciated. Thanks!

Copper holy grail for embarrassing skin infections (and wrinkles, too)?

cybercoitus interruptus — Tue, 03 Mar 2009 15:36:31 -0800

Seeking info on the effectiveness of Cupron textiles, which are supposed to have wrinkle- and microbe- fighting properties due to being plated or impregnated with copper. Anybody have personal experiences with the pillowcases, bed sheets, towels, socks, etc, or can offer informed critiques of the company's studies? I saw the pillowcases at Bed Bath & Beyond yesterday and thought, "Sounds too good to be true, so I'll read up online before buying." I'm primarily interested in whether they really work against microbes because I'm having trouble getting rid of a chronic non-MRSA staph infection (yes, I'm doing everything my MD tells me, and have been for months, and tried alternative health approaches for good measure, all of which help but the lesions keep recurring).

I've read a couple of the articles by the company's personnel (scroll down to authors Borkow and Gabbay). "Biocidal textiles can help fight nosocomial infections" in Medical Hypotheses, and "Copper Oxide Impregnated Textiles with Potent Biocidal Activities" (proof only), from my lay perspective, seem sound (small pilot studies only, but still). I'd like to hear what people, who are used to evaluating science articles professionally, think of them.

(And if it really works on wrinkles, it'll make a great gift.)

Google turned up this hypothesis about the anti-wrinkle mechanism, this interview with Gabbay, and this article
that mentions a contrary opinion. Nothing about it on Quackwatch.

I will ask my dermatologist what he thinks, but since he flatly dismissed the idea that staph can be airborne or that it can be carried and transmitted by pets - well, ok, he didn't say it was impossible that I could have been colonized in these ways, but only highly unlikely. So unlikely as to be not worth considering in the arsenal I'm building of how to maximize my chances of getting rid of this, and minimize my chances of getting re-colonized from the same source (complicated backstory involving in-laws). Compared to what I've heard from my MD friends and read online, either his information's not up to date or he subscribes to a narrow view of how staph can be communicated. So I'm not going to rely on his opinion alone.

How to stain copper?

whatisish — Thu, 13 Nov 2008 08:52:27 -0800

I need to stain copper with a variety of different colors. How do I do this? Ok, so I suppose I'm mainly looking for a product that will stain copper. It actually has to stain the metal such that it doesn't change it dimensionally. That is, it can't be an applied product that creates a film or layer such as paint or lacquer. I need something available in a variety of vibrant colors.

Lastly, it has to be easy to use. It would be ideal if the product allowed me to submerge the copper to take the stain - like with easter eggs.

Copper pot maintenance and repair

Blazecock Pileon — Mon, 28 Jul 2008 01:57:01 -0800

How do I know if a tin-lined copper pot really needs re-tinning? Are there reliable re-tinning services in or around Seattle? The copper pot I have has some light circular scuff marks and very light (visible by tilting the pot at an angle) scratches at the bottom of the pot, but there's a 5mm dark spot around the inside edge near the bottom.

I generally use it to make custard bases and wine-based sauces, nothing too acidic. I use wooden and non-stick stirrers so I'm honestly a bit surprised at the damage — is the tin lining really this fragile?

Ultimately, I'd like to avoid copper poisoning when using this pot, but from what I have read about the marks I see, it seems inconclusive whether re-tinning is needed. Will re-tinning be necessary, and, if so, is there a competent, non-sloppy re-tinner in or around the Seattle metro area?

A penny for your thoughts?

1f2frfbf — Mon, 16 Jun 2008 08:01:43 -0800

What's a really good looking copper coin? I'm looking for a copper coin that I can polish up and give to a friend as a present. I don't want anything rare or valuable since I'm going to be polishing it using methods coin collectors would frown upon. Bonus points if it was minted in 1979.

Do copper peptides = copper, or are they something else entirely?

specialfriend — Thu, 07 Feb 2008 16:30:59 -0800

Can copper peptide use cause copper accumulation in the body? I'm using a product called Folligen on my hair daily. Its ingredients include cupric sulfate and soy protein, which apparently combine to become copper peptides. The manufacturer claims that the way the product is formulated, any free copper molecules are unlikely. I'm not so sure. Am I essentially bathing my head in copper every night, or is the resulting "copper peptide" something completely different and safe?

Copper pans and electric heat, do they mix?

aussicht — Wed, 30 Jan 2008 21:42:04 -0800

Can I use my three-ply (out-middle-inner) copper-aluminum-stainless steel pots and pans on an electric range? Will it mess them up?

Old Pipes

Juicylicious — Fri, 05 Oct 2007 14:01:26 -0800

Plugged Pipes - Is there a way to clean out the water pipes in my home without spending oodles of $s to replace them? I own an up/down duplex. The water pressure in the upstairs apartment is fine. The water pressure in the downstairs bathroom is horrible and getting worse by the day. It is so bad that I now have to hand fill the water tank for the toilet. The pressure in the sink and tub are getting progressively worse.

My handyman checked the pipe leading into the toilet and found it severely clogged. The pressure did not get better after cleaning. He has found a work around by putting in pipe from the sink to the toilet. It won't work long as the sink pressure is getting bad too.

I have majority old fashioned lead piping. It will costs thousand of dollars to replace with copper. Needless to say I don't have the cash to do it.

Are there any methods of flushing out the lead pipes?

I want a fancy pants fireplace.

stormygrey — Thu, 27 Sep 2007 10:16:39 -0800

I need to find a giant metal sheet, yet I am not rich, help? I want to wrap my historic fireplace in metal. I like the look of copper, but I am flexible. I want one big sheet that is pretty easily molded so I can use a press to make the corners, attach it to a basic armature and just slide it over the fire place without any additional attachment. It probably also needs to be a place that would custom cut it. It needs to be 8 feet by 4 feet 1 inch if that helps.

I really want a nice clean look, so I don't want to try and fit several pieces together or anything.

Does anyone have any experience in this or know of some trick I could use that I wouldn't know about?

I found a place that could get it for me for in copper for about $550, but if we make any mistakes we are so screwed.

I am in Atlanta and have a pickup, so I can drive to get it.

As an unmuddied lake, Fred. As clear as an azure sky of deepest summer.

[expletive deleted] — Sat, 14 Jul 2007 02:08:06 -0800

Why did my garlic turn blue? I was cooking salmon on the barbecue yesterday and when it was done I noticed the garlic had turned bright blue. I looked it up and it seems that garlic in pickling solutions will sometimes turn blue. There are various explanations of this, but the most common one is that in an acidic solution, sulfur containing compounds in the garlic react with even minute amounts of copper to form copper sulfate. This is what I had assumed had happened, because I remembered hydrated copper sulfate being exactly the same colour.

There were a few other explanations of how the colour forms, but assuming that this explanation is correct, where did the copper come from? The other ingredients were soy sauce, rice vinegar, ginger, and slices of apple on a wild sockeye fillet. I cooked it in tinfoil.

I apologize in advance for what is probably a trivial question. It's just been bothering me for a whole day now.

Mystery Cable: Better used as rope, or sold to tech firm?

Quarter Pincher — Tue, 15 May 2007 06:55:19 -0800

TeleComTechFilter: I have recently come into the possession of a number of lengths of think coax-looking wire/cable. Are they worth much anything? Basically a hand-me-down that I have no idea what to do with, I am now in possession of three largish heavy wooden spools of cable/wire that have these weird letters on the side, and I was hoping the hive mind might be able to tell me (a) what they are (b) what they're for and (c) are they worth selling someplace like eBay..?

The little numbers/letters along the sides are thus:

"BELDEN-M 1057A E-34972 8PR20 1C22 SHIELDED (UL) CL3 105C PLTC 300V SUN RES 1112"

"SUPERIOR ESSEX W 1999 25 PR 24 UTP (ETL) CMR c(ETL) CMR ETL VERIFIED CATEGORY 3"

"FEMCO W12912 E73202 (UL) TYPE TC - TFFN OR THHN OR THWN 600 VOLTS SUN RES ART 340"

They're coated in plastic skin (two of them black, one of them [the essex] is beige), and when stripped, have all manner of little copper strand layers, various other wires enmeshed inside, etc.

The place I got them from installs alarm systems, audio/video, cameras and other electronics.. if that helps any. I would estimate the two blacks at appx 100+ft, while the beige (essex) is likely more like 300ft.

I can take pictures of a stripped end of each, if needed.

Coppery/iron-like smell in the air after it rains?

shivohum — Fri, 06 Apr 2007 20:21:59 -0800

Where I grew up in a suburb of LA, a coppery/iron-like smell, reminiscent of pennies or blood, would always waft unpleasantly through the air after it rained. I could never locate its source. Has anyone else had this experience, and what causes this?

Copper disks/slugs

glip — Wed, 07 Mar 2007 07:58:07 -0800

I'm looking for a supplier of copper slugs or disks, 7/8" in diameter, 3/16" thick. Does anyone know of a company in Canada or the U.S. that ships to Canada. I've been cutting them from round stock but that is time consuming and wasteful.

Alternatively, is there another name for small round metal disks that I should be googling?

Copper Copper Copper China

strangelove — Thu, 08 Feb 2007 12:34:53 -0800

How (where) does one go about procuring 100mt of copper for shipment to China from North America?

Where in SF can I get a Moscow Mule in a copper mug?

soda pop — Sat, 27 Jan 2007 18:29:33 -0800

Where can I find a Moscow Mule in San Francisco, complete with obscure copper mug? IF you can answer and you're in the SF area, I'll buy you a Moscow Mule too (more inside). SF Idiosyncratic Lush Filter. I've been trying to find a bar that can serve a Moscow Mule in a copper mug. The few places that have the ginger beer typically don't have the copper mug (see, e.g., Hobson's Choice). Surely, with Bourbon and Branch and Alembic bringing the Aviator, the Old-Fashioned and other "old-school" drinks back, I should be able to find a proper Moscow Mule in SF proper. I'm even willing to go to the East Bay/South Bay (this, sirs, is a cry for help--I once considered SF to Walnut Creek a "long distance relationship.").

How do I ground copper water pipes to old iron water pipes?

kuujjuarapik — Thu, 28 Sep 2006 11:29:08 -0800

How do I ground copper water pipes to old iron water pipes? I have an old house where the oldest plumbing is iron, and the newer plumbing is copper. I want to fit in a water filter on the iron pipe, but use copper fittings. I have heard that if they aren't ground properly they corrode. Unfortunately, replaceing the iron pipes is not an option.

Bonus question: can you solder copper fittings directly to iron pipe?

How much copper in an average PC?

nyterrant — Thu, 18 May 2006 12:12:16 -0800

How much copper is there inside an average PC? I'm trying to find out how much copper, palladium and other valuable metals are contained inside the average PC. I'm most interested in copper, but info about any other valuable metals would be great. Can anyone point to some good sources on this?

The mystery of the bathroom

Big Fat Tycoon — Mon, 19 Sep 2005 10:56:51 -0800

What's this blue residue in my sink and tub? In my new apartment, I've noticed over time a visibly blue residue build up in the bathroom sink and the bath -- they're both white so it's quite obvious, but I'm not sure if it's happening in my kitchen sink. I did some basic googling and found that people talked about over-acidic water possibly corroding copper pipes and causing this, but I asked my landlord who lived in the place just prior to me and said he's never encountered the problem. Could it possibly be the soap I'm using? Why does it only seem to leave a residue in a particular pattern, instead of over the entire span of the tub? The residue can be rubbed off pretty easily, but comes back after a few days.

Keeping Slugs out.

retro88 — Tue, 03 May 2005 12:19:30 -0800

Does anyone have tried and tested tips for keeping slugs and snails out of the garden? I live in the northwest so there are a lot of them. I have heard using copper wire is a good barrier. Any ideas on this?