A "gold dredge" is a mechanical mining tool that extracts gold from sand and gravel by sucking up sediments from the bottom of riverbeds. Synonyms for "gold dredge" include "dredging machine," "mining dredger," "gold mining equipment," "gold excavator," "suction dredge," and "gold panning machine." These synonyms describe different variations of the tool, from manual hand-operated dredges to large industrial machines. Gold dredges have been used in gold mining for centuries, and many different types and designs have been used over time in various countries. The common denominator for all of these tools is the desire to extract gold and other valuable minerals from riverbeds and other waterways.