vegetable

not edible to humans although it wouldn't kill you if you did eat it

"a" vegetable isn't a clue

not a carrot

Is a product made from vegetable materials

Not made of wood

something manufactured

Floats on water

not made of paper

not something made by humans in order to travel on water

Nowadays it is both manufactured by hand and by automated process

does not have moving parts

Not an item of furniture (including a table)

Not woven

Chalky does not currently own any

not wicker work

not a piece of clothing

not machine washable

has a specific colour

depending on your definition of middle ages, they might or might not have had it then

didnt have them in the stone ages

not usually larger than a phone book but extreme examples might be

manufactured for specific purpose or function

not white

not from the husk of a nut

not orange (but orange is close)

Not coal

not a book

It readily combusts

is not amber but as a colour is close

not a charcoal biscuit

is produced from a particular vegetable

A tennis ball?

ZK - No, nothing to do with wax
Dujon - No
Inkspot - No

I'm trying to think of a clue that doesn't give away the answer, although 24 hours is probably quite long enough to be guessing something as straightforward as this. The recap didn't mention my clue so to reiterate: Tuj's question should lead you straight to it. The ambiguity of its 'edibility' is also relevant.

Oops, it's already been said to be not a liquid.