The message .com
from "Rajiv India" contains these words:

Hi
This is Rajiv, from India.
I have a question - Which colour hat - Black or white - is better to
beat the heat and sun?? Especially when you are in agricultural fields
for hours at a stretch...

Sounds silly, right?

Having tried and tested many sunhats, no it doesn't!

The best I ever had, was lined (crown and brim) with dark green
material. It suffered a fatal injury in Australia. Currently, I have a
white one (cricket style, lined dark green) and a grey-green "French
Legionnaire" style one which claims to be lined with some kind of
UV-reflective material and gives good shade to the eyes and back of the
neck while I'm bent forward gardening.. The greygreen one is definitely
cooler.

Janet.