On the left, Spica in crêpe de chine in Andesite (black and white monochrome) and on the right Indigo (deep blue gray to pale gray and periwinkle monochrome) right out of the box.
Look at Andesite. At the top left, it is very charcoal. But at the bottom right corner, where it overlaps the Indigo version, it almost seems to take on a little blue.
And that's silk for you. Some of that little shift relates to the almost sparkly, indefinable translucence of crepe de chine, a most delightful silk. But the rest just has to do with the structure of silk itself. Its fiber structure is triangular and therefore prismatic. That means it is always going to pick up just a little bit of the colors around it, which is great for blending with you and the rest of your wardrobe.
Here they are side by side without any overlap, folded, and very slightly separated at a more saturated point in the image:
Your monitor may display the image color slightly differently than mine, but you can see that the color difference here is quite clear. Which just provides another way you can play with silk!
SILK GEORGETTE: lightweight, matte, filmy, and semi-transparent. Romantic and dramatic. Brilliant in warmer weather and a great layering piece year round.
12 MM CREPE DE CHINE: slightly heavier and translucent with beautiful drape, depth, and subtle shine. Great year round.
ANDESITE MONOCHROME: a subtle, sparkly palette of blacks, grays, and whites.
INDIGO MONOCHROME: just as graduated but slightly bluer and cooler, moving from deep, saturated indigo gray to pale blue gray with a touch of lavender and white.