Jumping on the bandwagon of what a cool feature you have. Working with your current paint color, I'd play with it along these lines -- cursor over for wide view.

(Etsy sources: http://www.etsy.com/search/handmade/art?q=black+brown&view_type=gallery&ship_to=US )

cool feature - paint it if it is too dark but add a cool mantel please it could be a show stopper

I love it! What a fun funky feature. decoenthusiaste, I was thinking the exact same thing. Play up the circle theme and have fun with it. Your guests will be thrilled to stay in the circle room. I actually think this will fit in easily with a modern esthetic and I can foresee this becoming one of your favorite features of your house.

Amazing and one of a kind! I love the confidence of the long-ago architect and mason to create this unique feature.

I like it! It makes me think 'Eastern' at first glance, like one of the windows I saw in the Great Wall. I wouldn't paint it; that would be an aesthetic crime. You can leave it dark but brighten the room with other accessories.

Is this fireplace distant cousin of that famous monster fireplace ? :)))))
https://www.houzz.com/discussions/monster-of-a-fireplaceive-never-seen-anything-like-it-dsvw-vd~323878

Please. It is begging to be painted with a whitewash flat paint . Also with the slope on the brick along the bottom , it looks like anything , including candles might just roll on outta there . Please get some battery operated LED candles for safety . they are fabulous & look real . Some have the led lights down inside a melted candle shape.

What a beautiful and unique fireplace! I'd definitely leave it natural, but make it a focal point like others have suggested and surround it with minimal things as to not overcrowd the area. I like the idea of a comfy chair and a small table like leelee suggested.

It's great from a Feng Shui point of view. "Circle in the Square" and with the element of Fire! Very nice. See what Gua the fireplace is in as it could also be overpowering, esp. in the bedroom. Or it might heat things up!!

This is a spare bedroom, so no one is sleeping in it, we use it for guests. I put the bookshelf there because I want that corner to be a reading nook, I just haven't bought the chair or overhead lamp yet. I will post some other photos at the weekend of the rest of the room. The room is at the front of the house and has a verandah in front of the bedroom window which means the room is very dark already, I feel the fireplace really dominates due to the colour. The bricks were originally glazed but as they are almost 100 years old, they are worn and chipped. I could varnish them which will reflect what little light we haven but it still is imposing. What I really am interested in, is how to dress it???

How old is the home?

You can't have a functional fireplace or wood stove in a bedroom according to the most over arching code (I believe). The exception might be an historic building, but one of those would be unlikely to have a circular fireplace.

We use wood stoves and I can't even feature what was driving the "design concept" since the hearth is nowhere close to being safe, let alone "to code". I instantly look at fireplaces and stoves with respect to functional safety. Any fireplace becomes an "attractive nuisance" when power failures render homes cold. And people who know zippo about burning wood die as a result. Because we burn wood regularly I am "big" on safety!

I'd figure out how to effectively block the flue and render it functionally inoperable since it's not SAFE. Then? I'd treat it as an interesting piece of "art". Personally? I'd eliminate it altogether and wipe out any notion of using it for "ambiance"!

It's a 1920's home and we were never intending to use it. I have already blocked it off to prevent cold/heat and worse, spiders from coming into the house.

I have never heard of not being able to have a working fireplace in a bedroom, at least in California. We used to have one in our master and our house was about 50 years old. I would never get rid of this beautiful fireplace. You certainly can have it inspected to insure it's safety before using. Also I would not paint it, just clean it up a bit and I think you will be pleased with the results. Good luck.

We are in australia so it would be quite rare to need the fire in a bedroom when we have reverse cycle air con/heating.

Unique in a good way. Would leave it as is, think it would blend more if you did built in bookcases.

the idea of adding a circle theme would in my opinion render way too many circles! except for the one rug that someone pictured. I love the ideas of Barnhart Gallery...

Since your home was built in the 1920's. do some research and find out more about that
fireplace, it's amazing!

Wonderfully unique--I'd play it up. It is such a strong element that it stands on its own just fine. So, I agree, relocate the abutting shelves and consider a pair of vertical elements (cupboards? shelves?) that do not fully occupy the space on either side of the fireplace. I cannot quite make out the room colours (which vary on a computer screen in any case) but the walls appear to be a shade of grey. I suggest drawing out the floor with wall colours that complement that wood. Your mantle could match the wood, or the new trim which should complement the new wall colour. Great room!

how high up is the mantel piece we're seeing?

I think that a mix of older like fireplace/culpture/vase/etc with modern furniture could make a very cool combination. I think the mirrors suggested above will help.
If you go with the suggestion above to warm up the colour of the walls (which I like). I think you could add some ceramics to tie the fireplace colour to the lighter warm shades. Some pics attached for inspiration

What a beautiful feature. Please don't paint it! I agree with another comment to paint the room or at least that wall in rich colors that will compliment the brick glaze. Go for Arts and Crafts type colors, which are generally more "muddy" than bright or clear. If you have an artist friend, get him or her to touch up the chips to match the glaze. You also need to put trim around your hearth, wide enough to at least reach the edge of the brick part. Any carpenter can do it. Extend the mantel to form the top of the bookshelves (keep the wood chunky), and have the bookcase reach from fireplace to wall. Get some big fat handsome silver candlesticks for the mantel. Pottery vases with an attractive arrangement of branches in them could go on the hearth. again arts and crafts style, but the vases in brighter colors, like deep red, turquoise, chartreuse. Take the little fiddly stuff out of the fireplace and leave it empty or put some pretty logs there, like birch.

another

I think if there is space a brown leather chair would would be great (for your reading nook). One with lots of depth of colour in the leather would be nice. The pic is not the right style of chair but it shows what I'm trying to explain by "depth of colour". I would pick the brown for your room keeping in mind the brick colour (so they are harmonious brown shades)

I feel like something more needs to be done in fireplace opening, rather than the pine cones. Houzz folks, any ideas?

I was thinking at least interesting logs but I think birch is probably too bright and not in harmony with other proposals, not sure if in your geographic area there would be other types of tree logs with darker but interesting bark.

Put a recirculating fountain inside it that is battery operated .

I love your fireplace! I would make it the highlight of the room and clean off the mantle and surrounding area. Perhaps a lighter marble or an interesting geode top and lighter rug? If it is non-functional then I might consider putting a vase with flowers in the opening. I would not paint it for in so doing, I think you would mask its mysterious charm.

(If you do paint it, an idea would be to paint it white and get a custom fireplace screen that is decorative/art itself. [use google enter: "decorative fireplace screen" and select the images option at the top, and you'll see what I mean])

Mmm, a few good ideas here. Maybe some nice looking eucalyptus logs, perfectly cut to go under the two iron bars, then possibly a piece of glass made to sit on the bars and then candles of various sizes on the glass which when lit will provide its own ambient light. I think I might varnish the bricks first, see if that helps, then if that doesn't look much better, paint it. I will definitely post some more photos of the rest of the room at the weekend. I am definitely not redecorating, because we have used different strengths of same paint in the front part of the house and I've spent money on curtains, throws etc, but a chair and reading light might work well as suggested, next to the book shelf. Keep the ideas coming, a plan maybe evolving here.........

I like the fire screen idea with an Art Deco design due to the house being 1926. If you mounted insect mesh on it and inset it to the hole, it should cut the spiders and other insects numbers.

karlagotting: This almost seems like you've inherited a very large art piece. It's pretty darn cool, so I'd leave it. I'd keep it light and simple in the room, but balance the dark mass with something dark opposite...the bed headboard, for example. What if you did a fine screening around where the damper would be (spider prevention), and did something like a round mercury glass type inset at the back of the fire box? A few candles, and you would have an interesting look without flames. Some trailing plants in simple white or silvered pots on the mantel to give it a little life.

3,6m high ceilings, huh?
I think you can get away with brown ceilings.

Pick a paint chip that matches the fireplace tile, but without the red tones in it.

Painting the trims and shelves black would certainly help too.

It's either less contrast by pulling the other surfaces closer, or creating more contrast throughout the room. If you don't want the fireplace to be the single strong feature of the room, create more (counterbalance).

It doesn't need painting.

The vases would look great with this fireplace. The fireplace has a look of being an oven for blowing glass and it would look great with them. I still think this fireplace begs for some hints of industrial style.

igosangwa had a good idea to add a rug at the base of the fireplace to cover the dark hearth but don't go too big since the floors are so pretty. Something with the wall colors would be lovely.

I would paint it a chocolate brown espresso color, then paint the mantel a driftwood gray/brown color to complement the wall color. I would put a driftwood sculpture in the center. If the fireplace wall is a bumped out wall, I would consider painting just that wall, a slightly darker color than your current walls. I would paint the bookshelves that slightly darker color. Then I would do a small poured concrete base to span the wall (covering the current base) and creating a connection to the bookshelves. Then a driftwood framed mirror above. http://houzz.com/photos/4028244

Maybe you can be inspired by other round fireplace designs - http://www.digsdigs.com/unique-round-fireplace-to-make-your-space-cozy/

i'd not paint the bricks!!!! i would however paint the board that serves as mantel. i too would nix the bookcases. the room would be nice in earthy tones and organic materials. so many folks above are on this same track. it's a unique feature that is actually quite well made. it cries for block and bold, not pencilthin and airy. if you must do bookcases in this room choose a different area and make them substantial. everything must have some heft to it to work in here.

interior styling of this fireplace needs heft also. the small pinecones small candle are too.... small. think chunky. three round pieces of firewood (ie not split) would be nice.

1930s is probably my favorite style. i really envy you this home and fireplace!

Art Deco style:-

http://www.mokumtextiles.com/metropolis---catherine-martin-by-mokum

"we have gone with a contemporary/modern feel throughout the house that emphasises period features."

It's gorgeous. Don't remove the old patina, just dust. Build an inglenook around it. This could be done by dividing an old church pew. Soften the benches with knit or chenille pillows, thick cushions and a fluffy throw.

Put an accessory vignette in it: battery or oil lamp, plant, a few of those books, statue or whatever.

Or you could put a large collection of candles or 3 oil lamps in front of the mirror.

Shine a spot-light on it from the other side of the room. Clamp lights from the lumber yard are great for this.

And yes a rug, but not too bright or busy so as to steal the thunder from the FP.

The fireplace is really cool!

I wouldn't paint the brick, although I would be tempted to strip and oil the mantle shelf. I am curious about the black hearth strip at the base, it sees almost like something put in later. What a fascinating thing to have in your home...

The round shape of the fireplace brings the metal element in...I kind of like the idea of possibly taking out the bookshelves (from a Feng Shui perspective, not great to have pointing at your bed), putting a cosy chair with curving lines with a small round table and lamp in that corner, and keeping the room calm and clear. A nice neutral palette, perhaps a bed of iron or wood in a simple design, some soft textiles to give the room softness and warmth.

It's a great feature to have!

Removing the fireplace is a valid option. You don't have to remove the chimney, just the interior workings. (this will give you the option of adding something smaller, later) We Americans place a lot of value on fireplaces, even in places they are not needed. We just removed a behemoth fireplace from our living room, that was taking up almost 30 square feet of floor space. The fireplace had never been used, in the 25+ years of the house's life. Our neighbors (some have fireplaces, some don't) can't understand why-"Where will the holiday decorations go?" Ummm, the same place they'd go if we didn't have a fireplace. Bottom line, your house, your choices. I will say, if ours looked as good as yours, I'd be tempted to keep it, if only for the "that's so cool!" factor.

Bad me, you wanted to have this area for reading....
Ok, on the shelves...if you could cover them with doors to blend in and make the shelves less obtrusive...would that be something you could consider and find of use?
I just feel the shelves as they are, aren't good for a sleeping room.

Enjoy it, consider yourself lucky, it's stunning just the way it is. Go with a darker romantic feel to the room and really play up the fireplace. It would be a shame to alter it.

Rachuba also made a good point. Some of us see that as a really cool feature, but if you don't, and you need the space...

Your house, your call...

And by interior workings, I mean the structure of the fireplace that is in the room, the brick, the hearth, etc.

Odd fireplace. Looking at it makes me want to form the word/letter "O". Would find that annoying very quickly.

That chimney will probably cause you to lose a lot of heat in the winter.

If you're not going to use the fireplace as a fireplace, have it removed ... and, perhaps, reuse the brick in a patio or as a retaining wall in your garden.