Berkshire Mat boards are made by Crescent Paper Company. They are 4ply boards which make them about 1/16" thick.
Crescent Berkshire mat board is a low cost mat board that is about half the cost of acid free mats. These mats are not acid free mats. This board is a inexpensive board that still offers a buffered core and backing paper. It is listed on some sites as a acid free board, but we would emphasize its usefulness only as a decorative board. The core is a cream color and can darken with age. They are what furniture framing companies use for production framing.
Picture Frame Mat samples are 2"x4" pieces of mat board that are for people who need to make sure that the mat color they see on their monitors are true to life. We have made every effort to make the mat board colors look as close as we can to their true colors but they are not perfect because everyone's monitor colors come across a bit different. There are over a million whites in the world so showing you the subtle differences online is impossible. If you need to make sure about the mat board colors before you order mats then we highly recommend ordering mat board samples so you can be sure the colors are exactly what you need.