Carilah huruf "F" atau kata "Fenton" di bagian bawah benda. Carilah ukiran "Vallerysthal" atau "PV" di dasar barang. Cek ukiran "WG" atau buah, burung, dan/atau bunga pada barang. Identifikasi produk Fostoria melalui takik atau label kertasnya.

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Fenton milk glass is known for its ornate pieces with raised bumps and frilled edges. Most Fenton pieces will have an "F" or "Fenton" engraved inside of an oval on the bottom side of the item. If your item has this engraving, it could be genuine.  After 1980, Fenton started to put a single number after the "F" or "Fenton" engraving, to denote the first number in the decade. Therefore, all Fenton glassware made in the 80's has an "8" after the "F" or "Fenton." Fenton has been making glassware since 1905. If "PV" or "Vallerysthal" is a raised engraving on the bottom of the piece, it may be a genuine item from Vallerysthal Glassworks of France. Typically, these pieces are a bluish-white color and are made into glass animals or shells.  Some newer Vallerysthal pieces have a sticker that says "PV France" on the bottom of the item instead of an engraving. Vallerysthal Glassworks was founded in 1836 in France and still makes glassware today. An engraving of "WG" on the bottom of the item means that the product was produced by Westmoreland in America. They are known for their rimmed edges and grape and floral designs.  If the "G" overlays the "W" in the logo, there’s a good chance that the item was produced before the 1980s. Westmoreland made glassware from 1889-1984. Fostoria pieces typically have a paper label that denotes the brand; however, older pieces may be missing the label. Luckily, most Fostoria pieces have the same sort of engraving--an ornate crossing pattern that creates raised triangles on the surface of the piece.  Not all Fostoria pieces have its famous pattern. Fostoria usually makes vases, cups, and bowls. Fostoria made glass from 1887-1986.