Use
Check tags were a system for tracking miners, by number, as they entered an underground mine: Tags were removed from a board by each worker as he entered the mine, and replaced on the board when he exited for the day. This let the company know how many miners, and which ones, were in the mine at any given time. They were also used for coordinating the weight and payment for each cart of coal that emerged while the miners were still working below: a miners hung their numbered brass tag on each coal car they filled, so that the checkweighman knew which individual miner to credit with that cart's load.
Also known as miner's checks, pit tags, pit checks, and time checks.
