Main Difference
The main difference between Emerald and Teal is that the Emerald is a green gemstone, a beryl variety and Teal is a low-saturated color, a bluish-green to dark medium, similar to medium blue-green and dark cyan
Emerald
Emerald is a gemstone and a variety of the mineral beryl (Be3Al2(SiO3)6) colored green by trace amounts of chromium and sometimes vanadium. Beryl has a hardness of 7.5–8 on the Mohs scale. Most emeralds are highly included, so their toughness (resistance to breakage) is classified as generally poor. Emerald is a cyclosilicate.
Teal
Teal is a medium blue-green color, similar to cyan. Its name comes from that of a bird—the common teal (Anas crecca)—which presents a similarly colored stripe on its head.
It can be created by mixing blue with green into a white base, or deepened as needed with black or gray. The complementary color of teal is maroon. It is also one of the initial group of 16 HTML/CSS web colors formulated in 1987.
The first recorded use of teal as a color name in English was in 1917. The word is often used colloquially to refer to shades of cyan in general, including the color cyan itself, most notably in computer games, where one of the players is given the colored cyan.
Teal was a fad color during the 1990s, with, among others, many sports teams adopting the color for their uniforms.
Emerald (adjective)
Of a rich green colour.
Emerald (noun)
Any of various green gemstones, especially a green transparent form of beryl, highly valued as a precious stone.
Emerald (noun)
Emerald green, a colour.
Emerald (noun)
A size of type between nonpareil and minion, standardized as 6½-point.
Emerald (verb)
To ornament with, or as if with, emeralds; to make green.
Teal (noun)
Any of various small freshwater ducks of the genus Anas that are brightly coloured and have short necks.
Teal (noun)
A dark, somewhat colour; a dark cyan.
“color panel|008888”
Teal (adjective)
Having a bluish-green colour
Emerald (noun)
a bright green precious stone consisting of a chromium-rich variety of beryl
“an emerald necklace”
Emerald (noun)
a bright green colour
“the sea glistened in shades of emerald and jade”
Emerald (noun)
a slender-bodied green moth, the colour of which tends to fade as the moth ages.
Emerald (noun)
a hawker dragonfly with a metallic green body.
Emerald (noun)
a small hummingbird with bright metallic green plumage and darker wings and tail, found mainly in the area of the Caribbean and Central America.
Emerald (adjective)
bright green in colour
“beyond the airport lay emerald hills”