An artist asked me for advice on qualities of rolled 300 lb. hot pressed lanaquarelle paper she is using. She noted a distinct sparkle that could almost be described as a glitter effect in certain lights. This paper is described as gelatin sized. What could be causing the sparkle ? Undissolved gelatin? Possible additives to harden the gelatin? The surface is softer than other 300 lb. hot pressed she has worked on that do not have the sparkle. I could not offer a good explanation.