What are the differences between matte/smooth & metallic papers?

The matte/smooth stocks generally have little or no texture at all, either in the way they look or feel. The exception to this is the cream puff and the snow white, which do have a very slight, feathered texture. 

Metallics are also known as "pearlescent," which have a shimmery finish.  The shimmer is subtle and is mostly noticeable when reflecting light.  The feel of the texture is smooth. 

Samples are always a great way to see and feel the premium quality.