Here I've included a pic. I wanted to find one where the satin was truly outside rather than a professional image that has most likely just an outdoor background. Here, the satin skirt is barely reflecting the man's suit...more like it's just refecting the light being blocked rather than the color or the object (not sure how to explain it). It will however reflect the color of an object, but only if it's very, very close. The sky just gives a whitish reflection. But, being raised by my grandmother who was a seamstress and being around satin all my life, and even tho it LOOKS rather metallic, there's more specular going on than reflections if that makes any sense. ;).

I realize the sunlight is very diffuse in this image rather than bright and hot, but that just makes the specular from the sky even more white than it is here. Of course, I know nothing about the math of all that ;).

Laurie