What is a good color contrast for these pillars
I think there's already a strong contrast in brightness, or luminosity, as the sari is much darker than the light golden pillars.

However, if you want to contrast the hue, then you'll want to find a color on the opposite side of the color wheel.

Since these yellows and oranges are very warm colors, their opposites will be cool purples and blues.

Here's some example color wheels I made. There's thousands out there, and interactive ones where you can select your color and find opposites. 



I would add though, that composition isn't always about contrasting colors, but finding complements, as well. 

And you can also contrast other elements of color, such as brightness I mentioned earlier, or saturation/chroma which is the intensity of the color. (So, less colorful, more towards grey, is desaturated or lower chroma).