Beautiful! It's impossible to know for sure but it looks exactly like my C. Irene Finney 'Spring's Best'. It's a spring bloomer and it was registered in 1964. Since you plan to mount it, keep in mind that it's very difficult to stake the blooms on a mounted orchid. It's best to mount cattleyas that have self supporting flower spikes. Just a thought. It's certainly a gorgeous orchid.
Oh THANK YOU all so so much! Orchidgirl...yes it's VERY fragrant and I can smell it from many feet away. Tucker...you may have a point there. The blooms are not self supporting so perhaps you are right about mounting it. It's just so big! The leaves and pseudobulbs are quite long.
For some reason however, the squirrels love to chew on the pseudobulbs of this one. It gets attacked every year so I wanted to move it into the Orchid House for protection.