Coral, often mistaken for a plant or rock, is a marine invertebrate forming intricate polyp colonies. These tiny animals secrete calcium carbonate, creating the hard, skeletal structures admired for their beauty. Distinguishing authentic coral from imitations is important for consumers, due to value, ethical sourcing, and avoiding misrepresentation. The allure of coral has led to a proliferation of imitations, driven by high demand and environmental concerns that limit natural coral supply.
Visual Clues
Visual characteristics offer insights into authenticity. Real coral displays natural imperfections like tiny pits, striations, or subtle grooves, hallmarks of its organic formation. These irregularities contrast with the flawless, uniform appearance of synthetics. Authentic coral also exhibits distinct growth patterns, resembling tree-like branching, visible pores, or a fine grain.
Color variations are another indicator; natural coral rarely has a perfectly consistent hue. It may show subtle banding, mottling, or slight color inconsistencies. Imitations often appear uniformly colored and unnaturally vibrant. Genuine coral’s texture is matte or slightly waxy, feeling smooth yet sometimes uneven due to its natural growth. An overly glossy finish, unless polished, might suggest an artificial material.
Physical Characteristics
Touching the piece provides clues about its genuineness. Real coral feels cool due to its mineral composition, similar to stone, and warms slowly. In contrast, some imitations, particularly plastic, may feel warm or quickly adapt to body temperature.
Genuine coral’s weight can be surprisingly light for its size, yet it possesses a specific density from its calcium carbonate structure. An unusually heavy piece might be glass; an overly light sensation could indicate plastic. Tapping the coral can also reveal its composition. Authentic coral produces a dull, solid sound, reflecting its dense structure. A sharp, hollow, or glass-like sound suggests an imitation, such as glass or certain plastics.
Simple Home Tests
Simple home tests can help determine authenticity, though caution is advised to avoid damage. The acid test, using a tiny drop of bleach or vinegar, leverages coral’s calcium carbonate. Real coral will show slight effervescence or tiny bubbles upon contact with an acid, indicating a chemical reaction. This reaction is subtle, not as vigorous as an Alka-Seltzer tablet dissolving.
The acetone test uses nail polish remover on a cotton swab. Rubbing a hidden spot of genuine coral with acetone will leave it unaffected. However, some fake corals, particularly plastic or resin, may become sticky, show discoloration, or transfer dye onto the swab. This test is useful for identifying dyed coral, as color may bleed from artificially treated pieces.
The hot needle test involves heating a fine needle and carefully touching it to an unnoticeable part of the coral. Real coral, a natural mineral, will not melt or produce a chemical odor. Conversely, if plastic or resin, the hot needle will cause it to melt slightly, with a distinct burnt plastic smell. This test carries a risk of damage and should only be performed with extreme care on less valuable or unnoticeable areas.
Common Coral Imitations
Various materials mimic real coral. Plastics and resins are common imitations, recognizable by uniform color, glossy surface, and lightweight feel. These fakes may also exhibit mold lines, indicating a manufactured product.
Dyed bone or shell is another common imitation. Magnified, these materials might reveal bone structure (fine veins, concentric rings) or distinct shell layers. Dye can sometimes bleed with acetone, and colors may appear unnaturally intense or uniform.
Glass imitations are heavier than real coral and feel cold, often producing a distinct glassy sound when tapped. They may also contain small air bubbles, a sign of manufacturing. Composites, made from powdered coral or other materials bound with resins, can be dyed and may lack natural coral’s intricate internal structure.