[TowerTalk] BLACKENED BRAID?

[K0DAN]

Seems I saw a post here within the last year that diagnosed the cause of
blackened copper shield?

My case: I have a buried run of Cable Experts RG213/U Mil Spec, supposedly
good for direct burial. It recently got nailed by the lawnmower (thanks to
the XYL!), but there's enough stub left above ground to repair and add a
connector, salvaging the buried run.

I looked at a few of the chopped up pieces and the copper braid is BLACK.
The center conductor looks normal, slightly dull copper color but in good
shape, easily cleaned with steel wool for solder/connector.

I would expect to see some kind of green or brown corrosion, but black? Is
this maybe silver plate braid and I'm seeing silver oxidation? Web site says
it's copper, not silver.

The cable otherwise looks in decent shape, and I do not believe it burned
due to high SWR or lightning.

I don't really want to replace the whole run but don't know the cause or
extent of the blackened braid. I have doubts I can clean it up and make
decent electrical connections but am willing to try.

RF loss is not an issue, any antennas on this line will be below 7 Mhz.

Ideas?

Tnx es 73

Dan
K0DAN