Hardwood grades. There are many different grades for wood but the most common is 1st and 2nd choice, also known as FAS (first choice/premium) and No. 1 Common/ standard (2nd choice). On the European market, the ipe decking boards are usually FAS quality. 2nd choice is used for construction such as the joists under the decking and other out of sight applications.
Hardydeck only sells FAS quality. FAS quality means no cracks, no holes and no sapwood. Warping is prevented by allowing the rough planks to dry for months. Ipe is one of the most stable types of wood that exists, but it is and remain a natural product. Hardydeck lets the rough sawn planks dry for an extensive amount of time, and if there are planks that are warped, these warps are planed out by the planing machine. Competitors often buy from unknown suppliers (who also subcontract), so that the aforementioned drying and production process is not completely under control. Hardydeck has the complete production line in its own hands.
FAS is not a ‘selected’ non-FAS wood. There are websites and (competitors) that will try to make you believe that FAS quality planks have been ‘carefully’ selected. This is just not true. The FAS planks are produced during the sawing of the log. By continuously turning the log, the sawmill (Hardydeck is a sawmill itself) cuts the FAS planks directly from the log. In production terms: “the sawyer looks for the FAS planks in the trunk”, with the sole aim of optimizing production. Defective planks such as cracks and holes are cleaned of all defects by shortening the width and length of the planks. This is the production process of FAS (and not the ‘selection’ of good from bad boards).
For more, see all grades of hardwood:
http://www.hardwooddistributors.org/postings/what-are-hardwood-lumber-grades-anyway
https://www.woodworkerssource.com/hardwood-lumber-grades.html