Duvet) Which one is warmer?

The goose down duvet I bought recently
is 30% goose down and 70% microfiber down lol
No wonder it wasn't as warm as real goose down.
When I searched for 80% goose down,
it was incredibly expensive.
I wonder if duck down with a high down content would be good,
or maybe wool,
camel hair,
or cashmere?
Anyway, there are so many options.
Which one is the warmest?