There are many manufacturers of fine watercolor papers. The preferred manufacturers of artist quality watercolor paper are from England, USA, France, and Italy. Each manufacturer has their special formula, but papers are generally made by making a fine pulp out of linen and cotton rags, then adding sizing and pouring this mixture onto a mold. Fine watercolor papers all have a manufacturer's mark, which is either embossed or watermarked into the paper and is apparent by touch or holding the sheet up to the light. Papers have two sides- Mold and Felt.
Fine papers come in standard sizes and weights.
The weight refers to the thickness or stiffness of the paper. All fine watercolor papers are acid-free, meaning that they have been treated to prevent decomposition. The texture of the paper is another important consideration.