Solid wood boards look where they fit with other boards. The seams run along the top and sides, while veneers usually use strips of sheet metal on the thinner sides of the furniture. If the table surface has lines on the top but not on the sides, it is probably a sheet metal. The touch, if the surface is not sealed, can help you discover if a piece is made of solid wood or veneer.
Real wood veins don't have a perfect, flawless grain pattern. If it varies and changes, it's most likely real. If you feel and notice a perfectly repeated pattern of veins, you are most likely touching a sheet metal or even a laminate of some kind. If the surface doesn't have any grains, again, it's probably a sheet metal.
Veneer is rarely used to cover the bottoms of tables or the bottom of drawers. Pulling out a drawer and checking the back and bottom will show if it's made of wood products rather than solid wood. By looking into the space left free by the drawer you took out in a dresser, sideboard or sideboard, you'll discover what the interior partitions, the back and the bottom of the countertop are actually made of. Likewise, checking the underside of a dining table or desk will clearly reveal what it's made of.
If it's plywood or OSB, the stamped numbers can reveal its origin and batch number. If you have an MDF core, you'll see an extension of grain-free material in gray, brown, or beige. In short, solid wood pieces and furniture will end up costing more than veneer instead of MDF or chipboard. In both cases, a surface that has the appearance of solid wood is glued to a less expensive artificial wood product, hiding it from view.
If the furniture you are considering has delicate and beautifully carved details, you are looking at an authentic and solid piece of wood. That's a deliberate choice on the part of many furniture manufacturers, since manufactured wood products are cheaper than solid wood. Later on, you might have thought you were getting a deal on solid wood furniture only to discover that it wasn't really solid when a scratch pierced the surface and revealed frayed fibers underneath.