Run the four questions
Can the construction be read? Is there usable footage? Is the insulation intact? Can ownership be released? Four yeses means sell as cable. Two or fewer means the metal value is probably the honest number.
Compare on the same basis
Scrap pays for contained metal by weight. Cable pays for construction, footage and condition. On a tagged reel of 500 kcmil copper the gap is large; on a bucket of unidentified cut-offs it is not.
Account for handling
Cable buyers collect, which has value where the alternative is loading a scrap trailer yourself. Factor that into the comparison rather than looking only at the rate.
Do not sit on it
Every summer outdoors reduces the reuse basis. A decision made this month is usually better than the same decision made after another year of storage.