1) Sandstone 2) Sedimentary rock 3) Type of sedimentary rock 
Siltstone is a sedimentary rock which has a grain size in the silt range, finer than sandstone and coarser than claystones. == Description == Siltstone is a clastic sedimentary rock. As its name implies, it is primarily composed (greater than 2/3) of silt sized particles, defined as grains 2–62 µm or 4 to 8 on the Krumbein phi (φ) scale. Silts...
hardened sedimentary rock that is composed primarily of angular silt-sized particles (0.0039 to 0.063 mm [0.00015 to 0.0025 inch] in diameter) and is ... [2 related articles]
An indurated silt having the texture and composition of silt but lacking its fine lamination or fissility; a massive mudstone in which silt predominates over clay; a non-fissile silt shale.
A clastic sedimentary rock that forms from silt-size (between 1/256 and 1/16 millimeter diameter) we
A fine-grained clastic sedimentary rock composed mostly of silt-size particles.
Fine grained sedimentary rock composed of lithified silt particles.
A fine-grained non-carbonate clastic rock compose of detrital grains of quartz and silicate minerals of silt size. Siltstones are rarely marketed as such but commonly are considered as fine-grained quartz-based stones (sandstones). Siltstone is texturally transitional between quartz-based stones and shales (mudstones). Many bluestones and siliceous...
[n] - a fine-grained sandstone of consolidated silt
noun a fine-grained sandstone of consolidated silt
A fine-grained non-carbonate clastic rock composed of at least 67 per cent of detrital grains of quartz and silicate minerals of silt size. Siltstones are rarely marketed as such but commonly are considered as fine-grained sandstones. This class of sediments is texturally transitional between sandstones and shales (mudstones). Many bluestones and