NARRATOR This over-life-size carving in marble is part of our Investigations tour. You'll see why when you look at the bands of drapery across the front. Here's Mark Abbe, from The Met’s Department of Scientific Research.

MARK ABBE: And if you look closely at the drapery to your right, if you're facing the front of the statue, you'll see a narrow band of purple on the outer edge of the hanging drapery that's adjacent to the figure's thigh. This band is visible only in this limited area that's sort of recessed and protected, but through examination, we know that this band originally extended along the whole of the garment. And in microscopic examination we can even see traces of gilding that's preserved on top of the purple paint. So we have here a really strong suggestion of the rich embroidery using gold thread brocade of the finest textiles of this era.

NARRATOR: Marco Leona is director of the Department of Scientific Research.

MARCO LEONA: In fact, we could see details like the gold only with a high powered microscope. And even with the best techniques at our disposal, we haven't yet been able to identify what this colorant is. The ancient Greek and Roman artists had an arsenal of materials at their hands. In a work of art such as this one, where the traces of pigment are both so important and so scanned, we have to work either by removing microscopic amounts at just about the diameter of a human hair, about 50 micron, or preferably by noninvasive techniques. In one word, by bringing the instrument to the work of art rather than taking a piece of the work of art and putting it in the instrument. So we've been using fibre optics techniques, laser techniques that allow us to conduct an analysis without touching the work of art.