This is why classic chrome or stainless is always the best choice for flanges and strainer basket assemblies. Even in kitchens where matching components is important, that’s an area where utility and practicality win out.

Do you have an antique strainer, or a 3 year old strainer? Or an antique strainer in a 3 year old drain?

Either way, copper has a tendency to oxidize and/or get icky from chemicals and even hard water. It's not really a good metal to use for a sink strainer. Very pretty when it's clean, but not efficient for keeping clean there.

You could replace with copper again- and not use the chemicals that seem to damage your strainer.

You could replace with a metal more suited to the task, like chrome or stainless.

If you don't want it to be plain old- perhaps consider using a brightly colored removable silicone or plastic strainer.

There is a good reason why chrome and stainless are typically the metals of choice for such.

Copper is a reactive metal. It will turn brown over time -- nothing can be done about this except not use copper.

However, they are copper basket strainers that hold up better than others. I don't know where to get one off hand, so I suggest you telephone the guy that does, Dino Rachiele of Rachiele sinks (800-881-9044). If Dino doesn't know, then no one does.

uh, I've had a copper sink/strainer for 15 years. mine still look brand new. I've used everything you can buy, cleaner-wise, and nothing has damaged the copper.

Have you tried scrubbing all of the gunk off of it? Letting anything sit for 3 years without maintenance is going to look like crap. you have to that every few weeks. get a stiff brush and some comet or bar keepers friend and scrub.

If it doesn't clean up, then that strainer part is not real copper. and if that actual colored portion has never oxidized, then that's not real copper either. you prob have a copper colored strainer that has corroded. copper does not.

CopperSinksOnline carry them.