A golden sample is a sample produced by a manufacturer that is perfect in almost all ways, so that when evaluated (by clients, competitors, inspectors, media, etc.) it can be tested and receive a high standard review. The term golden sample can also be used to describe a product that is a very rare find and is perfect in almost all ways and has been found just by chance. Contract Manufacturers and Original Design Manufacturers use the term golden sample to describe the final sample that is sent to the customer or OEM for approval before mass production.
A golden sample can also be defined in product testing as a sample that has all test results in the middle of the nominal range; such a sample sets the metaphorical “gold standard” not for product quality, because it is not a near-perfect specimen that a manufacturer should strive to replicate, but rather for usefulness in statistical comparison, in that comparison against it will reveal whether a mass-produced item is above or below the 50th percentile with respect to whatever attribute is being assessed.