Leigh's medium is the timber of the North Coast, particularly Australian Red Cedar (Toona Australis) and Rosewood (Dysoxylum fraseranum). His pieces are fashioned from the all parts of the tree particularly those parts rejected by those seeking straight grain timber for furniture - the buttresses and roots; the forks, knots and faults from the limbs; and the butt of the tree.

Red Cedar is now a very rare commodity in Australia. It is no longer available from State Forests and very few trees are felled privately. Attending private auctions and responding to personal contacts has enabled Leigh to accumulate 4 tons of Rosewood and over 2 tons of Cedar, some cut over a hundred years ago. This stock is very valuable - newly cut Cedar and Rosewood limb, butt and root off-cuts cost $400 to $600 per cubic meter ($40/cub foot). Seasoned and sawn timber ranges from $2,500 to $5,000 per cubic meter depending on age (or colour) and size.