Silk pillowcases are the best beauty pillow especially if you are concerned with frizzy hair, pimples, and/or wrinkles.
Concerning hair, silk pillows prevent static from the frequent movement as you sleep. This means less tangles, or if you have recently have had your hair blown out, it will stay longer.
Since silk is smoother than cotton or any of the other traditional pillows is helps to prevents creases and wrinkles on the face. It also contains many amino acids in common with the human body, these acids help moisture penetrate the skin (aid in absorption) and aid in skin healing.
Silk also has a naturally high content of copper which is an anti-microbial and can help those with ance breakout.
Branche is my favorite silk pillowcases. Found at the Four Seasons Hong Kong. The silk is extremely high quality, 22 Momme weight and the coloring in natural dyes.