Try a Mr. Clean Magic Sponge, or a paste made of baking soda and lemon juice. -Grainlady

Trica:
Of what material is the LC lid made??? ,
to cause the Black Mark.

I don't do too many abbreviations.
LOU

LC---Le Cruset, Lou. Enameled cast iron lid.

Try Barkeeper's Friend if the above things don't work. It's a bleach that acts as a reducing agent rather than an oxidizing agent....often works where Clorox doesn't.
But be gentle as it also contains an abrasive.
Linda C

It depends on what that stain is.

If it is food stain, bleach, or Easyoff may get it off.

But if it is other kinds of imbedded stain like enamel (from the LC cover) into porcelain, then nothing short of fluoric acid can etch it off.

Do not use any abrasive to rub it off. You may damage the shinny surface of the porcelain.

You may need to get a stone worker to polish the stain off using Lapidary Diamond Powder of progressive finer mesh. A stone worker can also take away any deeper scratches and re-polish the porcelain with a shinny surface.

dcarch

I have the white sink, you use Barkeeper's Friend...takes those black marks off like magic. Don't try that old Ajax/comet mess, it doesn't work, don't even waste you money on that garbage. I think the magic eraser sponge will work OK too but BKF is the BOMB!!!!!!!!!!!! It's my new(very old) miracle cleaner!

Some toothpastes are also good at removing marks.

Ann

Bar Keepers Friend's main active ingredient is oxalic acid. It can bleach some organic stains. Oxalic acid can also interact with iron and iron rust. Therefore, if the black mark is left by the cast iron lid, it may work.

If Ajax has been tried, which is mostly an abrasive, then it is unlikely that tooth paste will work. Tooth paste is a very mild abrasive compound.

dcarch

I second Dcarch's methods.
That's why I wanted to know what caused the black mark.

It is probably Cast Iron imbedded into the surface of the Porcelain.

It may have to be Polished, after the black is removed.

I'm not sure if Muriatic Acid would be another acid that might work.
If it is cleaned off with Barkeepers Friend, or an acid, neutalize it after,
with a Baking soda solution and see if it needs Polishing.

Before an acid is tried, check with the manufacturers technical support.
Ask what is recommended.
A pumice stone can be used to polish out some scrapes.

LOU

Ajax contains bleach.....depending on which formulation either chlorine or oxygen bleach.....and so does toothpaste.
Oxalic acid is a reducing agent and works well at removing metal based stains. Works well on blood stains (because of the hemoglobin in the blood) and meat stains on table linens. I've used it to remove stains when refinishing furniture....but it can be hard on your hands, so wear gloves.
I'll bet it'll get that stain off your sink.....and polish up your copper pans too.

Thanks for all the suggestions. BKF it is later this morning! I use BKF for my SS cookware but never thought of it for porcelain. I've also got a half Mr. Clean sponge thing stuffed in the drawer below the dryer I'll try if the BKF doesn't work. The spot looks terrible - your eyes go right to it. :(

/tricia

Well I have a very old white porcelain sink, everything that touches it leaves a black mark...I would never own another BTW if I had to pick a new sink out! Though the magic eraser sponge did manage to kind of get rid of the black marks, after reading many google results I found many people praising BKF so I went and bought the liquid and powder. They both work great...I was amazed at how good my old sink looked. Also the white sink is bad about staining yellow on the bottom, BKF gets that off like magic too! Unless your sink is chipped, BKF will clean it like new, I have no doubt about it. You should buy some pads for the bottom too or you'll end up with a chipped sink!

OK I just tried some toothpaste. I keepa tube of Colgate, the plain white paste one just for polishing things and I also have a tube of that Rembrante stuff. Both work reasonable well to remove the black marks on my old sink. The BKF works better as it removes all traces of the mark where as the toothpaste you can still slightly see it.

I go easy with the BKF on porcelain as it will etch (it's an acid) and it is abrasive. I use Bon Ami much more often. I will mix it with some bleach as it doesn't react and make a paste that can sit on a spot if needed. It is ever so gently abrasive.

Anytime you use an abrasive on porcelain, you create micro scratches on the surface and that makes the surface collect stain and require more frequent cleaning.

Porcelain is like glass, you can use most cleaners and bleaches, including "Easyoff". Most acids will not attack porcelain. Porcelain is attacked by glass etching acids such as sodium Bifluoride, and Ammonium Bifluoride.

BKF is mostly oxalic acid which will not damage porcelain. Oxalic acid attacks iron and rust. In this case, if the mark is embedded into the porcelain by the dropping of the heavy cast iron lid, it may be able to remove the mark. It may take time.

It is very possible that deep scratch is on the porcelain now. To remove the deep scratches on porcelain, you will need special technique and tools or call a stone worker. Those of you who are into lapidary and jewelry making will know what I am talking about.

Eventually and unavoidably, all porcelain sinks will have micro scratches all over the surfaces. It is not that expensive to invest in an angle grinder ($20-$50) and some diamond paste ($20) to polish up the sink back to new condition.

Diamond tools in my workshop I use to remove deep scratches in stone, glass and porcelain:

dcarch
{{!gwi}}

Barnmom....the acid in BKF isn't strong enough to etch your porcelain sink. And the abrasive is very gentle. I use BKF on my brass candle sticks and they will get mirror bright....no sign of abrasion.
But it will "etch" your hands and manicure! So wear gloves.
And BKF also removes rust stains from my stainless sink.
Beginning to wish I owned stock in the company!!!!
Linda C

It's good stuff but I did etch a stainless sink once by leaving it a water deposit for a while. And It is more abrasive than Bon Ami. So I keep BKF for really stubborn tasks like burned food in a stainless pot. An overnight soak takes it right out. And bad water deposits. And rust. I have seen sinks ruined by long time use of abrasives like Comet, Ajax, and BKF so I use those cautiously.

Well I'm not seeing anywhere that says that BKF is abrasive to the point of ruining anything. William Sonoma recommends it and I think if it's OK with them then it ought to be pretty darn safe. I've also seen that you can use it to get rid of the dull finish that happens to tail lights on your older cars. I haven't tried it yet but I'm going to. Also remember that the etching could also be caused by the cleaning pad you are using. BKF is not like comet or ajax at all!

BKF is my best friend in the kitchen! I have a very old old kitchen sink in my second kitchen that I use BKF on regularly. Then, in my newer kitchen, I have a beautiful porceline Kohler double chefs sink that I also use it on. I just can't bring myself to put those plastic divider thingys in my sinks...it sure would help keep the black marks down though.

Don't make the mistake of using Bar Keeper's Friend on your Le Creuset. Ask me how I know.

I use it on my Le Cruset....why not?

I'm wondering why some people are claiming to have problems with BKF...is it possible they bought something else and are just thinking they used BKF? I ask this because I was at the store one time years ago and picked up a can of Bon Ami thinking I was getting BKF(the product I'd seen raved about because I couldn't remember what the name was)...it did nothing to clean and is abrasive. I just can't imagine BKF ruining anything because I've used it on just about everything I can think of...the only thing that ruined anything was the scrub pad(the green ones) I used with it. It would have scratched even with plain water.

AK Girl - I "sacrificed" a knife to prove a point. Not the greatest pictures but the first one shows the knife relatively flawless, the second is after cleaning it with BKF. (Yes, BKF not Bon Ami.) Those long horizontal lines are scratches that do not come off now. Yes, I rubbed it fairly hard. I do like and use BKF, but I echo words of caution.

{{!gwi}}

{{!gwi}}

Doubting Thomas that I am....I just tried to mar a stainless spoon.....and couldn't do it. And I can't see any scratches in your pictures either....but that may be a fault of the photographer...;-)
I put the BKF on my wet finger and rubbed at the handle of a Stainless spoon. My finger got black showing it was reacting with the steel but could not see where I rubbed. I'll bet it would mar Sterling though....but not going to "sacrifice" a piece of silver!!

I accidentally put something in the DW once and got some rust spots on my old SS flatware. I little scrub with BKF and they looked like new again. I also have some All Clad pans a& they recommend and I use BKF. Nothing I have used it on has gotten marred or ruined.

In my above post I mean stainless steel flatware.

Well I took one of my clean nylon crocheted scrubbies that I buy at the craft fairs and used it plain wet and got scratches on my Stainless Knife with ZERO cleaner on the pad only water. I think those stainless knives are very easy to show a scratch. I used BKF on my stainless water faucet with a cotton cloth and it showed no scratch marks at all. It is a highly shined stainless Moen faucet.

There is no such thing as stainless steel.

There are many many many "stainless steel" types, and they are all stain resistant, not stainless.

dcarch

dcarch,

"There are many many many "stainless steel" types, and they are all stain resistant, not stainless."

Oh man, as a boater I can vouch for the truthfulness of that statement! I've spent hours & hours scrubbing various stains & rust from so called quality marine grade "SS". (grin) Our home's front storm/screen door is made from very heavy stainless steel/brass & powdered coated. It has to be powerwashed & scrubbed/polished every spring. (ugh)

Last night after I'd suggested the Magic Eraser or Bartender, DH shouted out, "Hon, can you come look? I got the spot off the sink!!"

You know guys, they'd rather do it themselves...especially when they caused the, eh, *issue*.

Anyway, here's what he used.

We use it to get fender marks off our boat's gelcoat. He figured if it didn't hurt Isle of Somewhere's gelcoat it wouldn't hurt the silly sink. He was right. So, I guess there's another weapon in the arsenal if anybody's else has black ugly marks on their porcelain sinks. We bought ours at West Marine but it might be available at hardware stores (but probably not...pretty sure it's a marine product).

/tricia

Here is a link that might be useful: 3M Boat Stuff