Card stock is a paper product that is categorized as being thicker and more durable than writing or copy paper but is thinner and more flexible than other forms of construction paper or cardboard. Card stock is produced in a variety of colors, surface textures, or coatings, and is sometimes referred to as cover stock or paperboard. Laser processing of card stock can be performed with either a 9.3 or 10.6 micron CO₂ laser without showing a significant difference in process quality. Laser processing of card stock using a 1.06 micron fiber laser is not recommended as this wavelength is not readily absorbed by card stock. Laser cutting of card stock results in a clean edge with minimal discoloration. Laser marking of card stock will produce an indelible surface mark with no depth which can be either lighter or darker depending upon the material processed. Laser engraving of card stock will produce both depth and contrast similar to laser marking.