Assertion: dredge | /r/ObjectUse | used in offshore and coastal placers
Facets:
value: mainly
type: DEGREE
value: with the exception of boulder varieties
type: OTHER
Source sentences:
text: Dredges are used mainly in working alluvial and eluvial-deluvial placers, as well as offshore and coastal placers, with the exception of boulder varieties, which are strongly cemented by rocks and viscous clays.