There's a smudge on the V-neck, right near the bottom of the "V" on the right side.  This occurred when I laid this sweater down and it touched the tip of my pen.  I couldn't get it out, so I've discounted this sweater substantially.

There's no tag on this sweater, so I'm not sure what fiber it's made of. The design would suggest alpaca, but it feels like it has some acrylic in it.  Could be a mix of alpaca and acrylic.  Either way it's so soft that it can be worn directly against the skin without being itchy.