New Galilee, Pennsylvania
Clay was an abundant resource in Beaver county. According to the 1955 circular of the Pennsylvania Geological Survey, In 1955 Beaver County produced 13.7% of Pennsylvania's total clay output. There were 13 companies that mined clay in Beaver county at that time. Two of these companies, The Negley Fire Clay Co. and Ralph A. Veon, Inc. mined fire clay of the plastic variety from open pits and marketed the output for use in manufacturing fire brick and block, foundries, and heavy clay products. In addition, Ralph A. Veon, Inc., mined and sold fire clay of the burley variety. In 1955, New Castle Refractories mined stoneware clay from an underground mine near New Galilee for use locally in manufacturing pouring channels
Clay
Although many naturally occurring deposits include both silts and clay, clays are distinguished from other fine-grained soils by differences in size and mineralogy. Silts, which are fine-grained soils that do not include clay minerals, tend to have larger particle sizes than clays. There is, however, some overlap in particle size and other physical properties. The distinction between silt and clay varies by discipline. Geologists and soil scientists usually consider the separation to occur at a particle size of 2 µm (clays being finer than silts), sedimentologists often use 4–5 μm, and colloid chemists use 1 μm. Geotechnical engineers distinguish between silts and clays based on the plasticity properties of the soil, as measured by the soils' Atterberg limits. ISO 14688 grades clay particles as being smaller than 2 μm and silt particles as being larger.