Projection prints are the most common material that is available to or found
in an archive, just as laboratories store the negatives and duplicates for
their customers. Occasionally when a collection that originates from a
laboratory is made available to an archive that are negatives and sound tracks
found.
Both colour and black and white positive copies have a clear base.
If it was a sound print, it may have either an optical or magnetic soundtrack; there also exist copies with both, called magoptical, in which part of the optical track is overlaid by a magnetic stripe applied after the film was processed [usually for an alternative language. Most archive prints are Release Prints; that is they were produced for display in a cinema or some other display location and were one of many that were originally produced.