Here's a good time to repeat this:
Here's the
chart of percentages of light reflected from Jorge's latest:
Foylon 94-95
Reflective Mylar 90-95
Flat white paint 85-93
Semi-gloss white 75-80
Flat yellow 70-80
Aluminum Foil 70-75
Black < 10
They say mirrors are not good reflectors because the light must pass through the glass, and that diminishes the reflection. But since you have a mirror-like finish without the glass, it might be up there around 90 percent.
HTH
