Assay Sampling Protocols for Industrial Metal Scrap Valuation
Assay sampling protocols establish true dry weight and payable metal content, directly governing settlement values, working capital allocations, and lender borrowing base limits.
Rotary Sample Divider
Meaning
Mechanical sample splitting equipment represents the device used to divide a bulk ore sample into equal, representative portions for laboratory testing. The rotary sample divider uses a spinning feed mechanism to distribute the material over a series of collecting buckets. This method minimizes the sampling bias that occurs when using manual splitters.
Splitting Mechanism
Material falls from a hopper onto a rotating feeder or into a ring of buckets. As the feeder spins, it cuts the falling stream of rock powder hundreds of times. This action ensures that any variation in the feed is distributed evenly across all the buckets.
The resulting sub-samples have the same chemical composition as the original batch. This high precision is necessary for both concentrate trading and ore control assays.
Representative Sampling
This machine is the preferred choice for splitting gold or silver ore samples. It overcomes the tendency of heavier minerals to settle and separate during the splitting process. This ensures that the analytical aliquots are highly representative of the bulk material.
If the split is non-representative, the downstream analysis is compromised.
Equipment Calibration
Technicians must clean the divider between samples to prevent cross-contamination. This is done using compressed air or vacuum systems. If the buckets or feeder are worn, the dividing accuracy is reduced.
This requires regular inspection and maintenance of the equipment.