Sunburn or more serious problem?

[steelheadr]

just received this pair of cattleyas in sheath from a commercial orchid grower, both grown strong & hard in lava rock. Note the extensive black patches on many of the leaves of the one on the left. Sunburn? Heat damage (though there is no wilting)? Rot? There are a couple soft spots within the black areas, but mostly they are just black. Almost looks like the areas near the black have been masked or shaded, thus my thought it is just a bad sunburn.

many thx for your help - a new forum member but a somewhat experienced grower,
Steelheadr