Vermiculite:Perlite ?

[Kirk]

Do either, both or none of these absorb/soak up water?

If I had say 2" of either in a pot stood the pot in shallow tray of water, say 1/4" depth, would either eventually have a damp upper surface ?

Just thinking of a potential germination option for next year.

[Bigmallly]

Vermiculite is used for water retention, Perlite is used for aeration although Perlite will absorb a smaller amount of water.

[Cadalot]

Here is a little guidance

[Ryez]

I had to look it up also recently. I have clay soil at the front of my garden so I mixed it with perlite and compost as water retention is not a problem with clay soil, but aeration is. My understanding is Vermiculite is good for germinating seeds as compost tends to dry out quickly.

So I guess, it depends on what you want to use it for.