Maybe it's only brass plated, rather than solid brass. Have you checked with a magnet?

Here is a link that might be useful: Is it brass?

It's definitely brass. I tested it.

Is it possible that the larger parts were lacquered and what you're seeing is the lacquer darkening instead of tarnish? If so, you'll have to strip off the finish with lacquer thinner.

Chibimimi is correct, they lacquer the pieces so that they won't tarnish so fast, but parts tarnish where the lacquer has worn off. You need to strip the whole thing, then polish it with a brass cleaner, but it will tarnish without a protective coating. If you aren't really fond of it, it's a lot of work. You might try taking it to one of those second hand stores, it might be just what someone else is looking for.

If its not a valuable piece you could try cleaning it with Simichrome polish in a small out of the way area first. It is not recommended you use this metal/brass polish on lacquered brass but I do and haven't hand any problems. As mentioned on some of this stuff some of the lacquer has come off and those bits tarnishe. I just use the Simichrome over the whole thing and it cleans it up nicely. I would use caution if your chandelier has value. Technically if it has a lacquer you are meant to use a spray paint remover and steel wool, wash and then the polish. However, maybe it does not have the lacquer. Are you trying to clean it with that awful brasso stuff? You will be cleaning till the cows come home with that.

Here is a link that might be useful: this is what you want

"I actually don't like the chandalier much at all but I'm hoping I'll like it better when it's shined up."

You might like it for a month or so, but then it will start to tarnish again. And again and again, which is the way of tarnish.

Yes, it becomes complicated....removing lacquer, relacquering or continuing to always polish or letting it complexly oxidize...

Get another fixture!

I bought a champagne bucket off of eBay. It was partially lacquered and yellowed. I brought it to a local silversmith and he polished it and took the lacquer off. Maybe you can call a local silversmith to see the cost? But if you don't like it much, you might not want to invest any money into it.

I ended up scrubbing with a green dish scrubbie and Wright's Brass Polish. It looks better(ish). Lol I wasn't able to get the thin rings that the shades rest in. Good enough for now.

I think it looks great, the green scrubby probably removed some of the lacquer. I think it looks better if it's not all one uniform color anyway, so the darker rings look good. If it's solid brass and not plated, another option is taking ultra fine 0000 steal wool to the tarnished areas next time it starts to tarnish.

Very cool light!

Oh my gosh I love it. It is so charming. I agree with kitchen that brass looks better if it isn't totally uniform.

Thanks guys! It's growing on me. We have quite a few hobnail light fixtures in this house so I'm going to learn to love it as it really does fit the house.

It's really attractive! Good job on the polishing!

Great job revitalizing the light, Louis!

Oh! Not at all the horrible fixture I was imagining.

It's very sweet. And it looks fresh, while simultaneously looking vintage -- a difficult look to pull off -- and you did it!

Nicely done.