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technical bulletins
Dig into the hard facts about natural reclaimed and quarried natural stone.
Whether you’re a landscape architect or installing contractor—you’re in the right place.
STONE CURATORS | TECHNICAL BULLETIN #1
Limestone Classes: What They Mean and Where to Use Each
For landscape architects specifying limestone and contractors installing it
Limestone is one of the most requested stones in architectural and landscape work for its warm color, fine texture, and timeless look. It is also one of the most variable. ASTM C568, Standard Specification for Limestone Dimension Stone, divides limestone into three classes by density. Lower-density, more porous stone (Classes I and II) can perform well on walls and cladding, but is prone to problems in exterior horizontal hardscape, where it absorbs water, freezes, meets de-icing salts, and carries traffic. High-density Class III stone is generally the right choice for exterior paving, steps, and coping. We call this “hard limestone”. The working rule: choose the class for the exposure, then confirm the specific stone with current test data … more
