As seen in the picture, a pencil polish is a rounded edge. It is the perfect edge for Glass Protector Tops because it blends into the edges of furniture.
Flat Polish:
As the name implies, a flat polish is a flat edge with a small 45 degree chamfer on the very top and bottom. For custom made 1/2" and thicker Glass Table Tops, a flat polish is recommended. It is economical and is the best way to show the thickness of the glass.
Bevel
Bevel: Beveling creates a decorative angle starting near the edge of the glass. For example, a 1" bevel will start 1" from the edge of the glass. Beveled edges are very economical on stock sizes, however, pricing becomes higher for custom cut sizes and is especially expensive on curves.
Seamed
A seamed edge has been sanded and it may be rough and slightly chipped, but it will not be sharp. It is the most economical edge but it's not recommended if the edges will be exposed.
Edge Defaults (unless advised otherwise):
Glass Protector Tops and 3/8 non-tempered custom cut sizes will have pencil polished edges.
All tempered glass and custom cut 1/2 or thicker will have flat polished edges.
Rectangular and square Stock Table Tops have beveled edges.
Other Edges: There are other edges available such as ogee, triple pencil polish (waterfall), wave, or chipped. Sometimes these edges are available on stock items but they normally have to be custom fabricated and are therefore very expensive.