All natural stone products are supplied untreated from the factory. The color and pattern of individual items can vary. In some cases, certain veins are treated with mastic (filled). This standard procedure is not only unavoidable, but necessary in order to supply a sound product. Certain types of natural stones need further strengthening. This is done by gluing a fabric at the bottom of the board. Therefore do not remove this reinforcement.
Natural fractures are commonly found in natural stone. They are not considered defects, but they may be filled with resin to create a smoother surface, this does not affect the quality of the stone product. You may be able to feel the minor groove and other differences in the stone surface texture but it is not considered a faulty product.