Identify this Tree

I was at the Brookfield Zoo in Chicago yesterday and came across this tree. Ofcourse, it was leafless at this time... and my wife and I are dying to know what species it is. The pastel colors on the bark is just unbelievable.

Looks like an old Chinese elm to me.

I should probably add... this picture is not photoshopped. The blue, orange, green, etc. all the colors you see is exactly what the bark had.

Russell,
From the light orange under-peel I can see why you said Chinese Elm, but what about the blueish bark with some slight green also found on the under-peel?

I believe Russell is correct. This looks just like many landscape lacebark elms that are everywhere here in Vegas.

Thanks Russell and MileHigh, good to know what it is. Thanks.