Things that appear to be black in the visible spectrum may or may not be black at other frequencies and this can have an effect on the overall amount of energy absorbed.
So what is the actual determining factor for how much photonic energy will be absorbed and converted into heat?
Here are some interesting references
that might illustrate how complicated the question actually is.
On a sunny day, roof temperatures can range from comfortably warm to egg-frying hot, depending on how much sunlight they reflect. Different roofing materials were tested side-by-side by Lawrence Berkeley Laboratory researchers; their peak temperatures are listed below.
* Black acrylic paint
: 142deg. F
* Galvanized steel
: 138deg. F
* Black acrylic
paint infrared-reflecting film : 123deg. F
* Common "white" fiberglass/asphalt shingle : 118deg. F
* Clay terra cotta tile : 112deg. F
* Red acrylic paint: 106deg. F
* Light green acrylic paint: 104deg. F
* White acrylic paint: 74deg. F
* Hyper white" acrylic paint : 65deg. F
Ambient air temperature at the time of the test was 55deg.F.