9 mm ≈ 3/8″ (7 plies) 12 mm ≈ 1/2″ (9 plies) 18 mm ≈ 3/4″ (13 plies) – From [3] Ultimate guide to Baltic birch. The core of regular hardware store plywood. Pretty bad in comparison.

thick core options veneer offer better stability than typical plywood with 1/8-in.-thick core veneers. The raw edge is attractive when finished and often used as a design element. Baltic birch or ...