The copper beech (Fagus sylvatica) is exceptionally ornamental because of its metallic-looking leaves. Any beech with purplish foliage may be dubbed a "copper beech." The trees' native range extends from central Europe to the Caucasus Mountains. Selection has produced copper beeches with an array of leaf colors, but all tend toward a coppery color in autumn before the leaves die and eventually drop off. Grow these trees in USDA zones 4 through 7.
The most common adjective given to the foliage of a copper beach tree is purple. Whether it's more reddish burgundy or purplish black, it refers to the base color being dark. Trees with purple foliage often have dark coppery leaves when they first unfurl from the buds in spring and then quickly fill with more pigment to reveal their mature leaf color. Some cultivars display their deepest mature leaf colors in late spring. Through the course of summer's heat and intense light, the pigments tend to fade and a casting of deep green is seen alongside the purple hues. Examples of selections of copper beech with exceptionally deep purple leaves are "Riversii" and "Rohanii."
The cultivar "Spatheana" (also sold as "Spathiana") develops deep purple leaves that are similar to "Riversii." The key difference is that "Spatheana" leaves tend to develop lighter, contrasting color veins on the leaf blade, according to the American Horticultural Society's "A-Z Encyclopedia of Garden Plants."
Dark purple leaves with deep rosy edges are found on the cultivar named "Purpurea Tricolor" (also called "Tricolor" or "Roseomarginata"). In late spring, the pink and dark purple leaves reveal their most intense coloration, but throughout summer the dark purple parts of leaves fade to dark greenish purple or deep green. The once-rose-colored leaf margins fade to more pastel shades of pink to creamy white. If too much direct sunlight reaches these variegated leaves, the white-pigmented areas readily brown, according to information in the University of Connecticut's plant database.