Have you considered square?

I'd say either square or round.

I vote for rectangular. Round on round seems rather boring and I'm not sure that I've ever seen a square rug. With a rectangular rug you're able to see much more of the pattern of the rug so in my opinion it would be more decorative.

The shape of an area rug is certainly a matter of preference or personal decorating style. One of the most important factors in selecting a rug for a dining room or any 'eating' area is the size. Where possible, try to make sure the chair legs do not get caught on the rug when sliding in and out. Another important factor, who will be dining with you? Do you have 'Messy Marvin', a house full of kids, or While natural fibers, like wool, are durable and elegant they are not always the easiest to clean. They are doing some amazing things with synthetic rugs these days. They look great, are very affordable, most are stain resistant and they can be sprayed off with a garden hose! Rug sites, like Rugs Direct, that let you narrow your search by shape, size, fiber, etc. might be helpful with your decorating dilemma.

Here is a link that might be useful: Rugs Direct

Have you ever tried to use rectangular shape rugs? I personally think that it is more suited to your round glass table.

Here is a link that might be useful: Area Rugs

Hey, Felix - is that ...
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Square rugs are available because I used to have one under my square glass table. You just have fewer choices. I have since replaced it with a round Karastan. I thought both shapes looked good with the table. I don't think rectangular would look as good, but I also think a lot depends on the shape of your room, the size and location of the table, etc.

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