Spectrum shapes color

Daylight, warm LEDs and cool fluorescent sources distribute wavelengths differently. Green may look warmer, cooler or grayer; lavender can be especially vulnerable to surrounding color and camera processing.

Olmec jadeite pendant, The Metropolitan Museum of Art
Open Access object image, The Metropolitan Museum of Art; public domain.

Direction shapes depth

Front light flattens texture; side light reveals relief and polish; backlight emphasizes transmitted light and internal variation. Use each deliberately, and do not present backlit appearance as ordinary face-up appearance.

Polished Olmec jadeite celt-pendant, The Metropolitan Museum of Art
Open Access object image, The Metropolitan Museum of Art; public domain.

A repeatable viewing setup

Use a neutral gray or white background, fixed distance and two known light sources. Turn off phone beauty modes and automatic color filters. Consistency makes comparisons more useful than dramatic illumination.

Emerald-green jadeite pendant from Qing-dynasty China, The Metropolitan Museum of Art
Open Access object image, The Metropolitan Museum of Art; public domain.

Research basis

Independently written from public information supplied by GIA, Smithsonian and The Metropolitan Museum of Art. GIA · Smithsonian · The Met