Gemstone grade and description chart.

Category: Gemstone Grades and descriptions.

Gemstone Index>

Gemstone Grades and descriptions.
Our Gemstone Grade Chart is easy to use. Here's how.
1. Locate "Gemstone" name.
2. View "Grade" Column for common quick reference grades used in the Jewelry trade.
3. View, "Description (industry standards)", terms used in the Gem Trade in Grading a gemstone.
4. Find the "AGTA Codes" in the right column. Click on it to go to the AGTA enhancement chart.

Gemstone Grade Chart
Gemstone	Grade	Description (industry standards)	AGTA Codes
Alexandrite	A	Light green to greenish blue, included, weak to low color change.	O
Alexandrite	AA	Green to greenish blue, slightly included, moderate to medium color change.	O
Alexandrite	AAA	Deeper green to bluish green, clean, bright to high color change.	O
Amethyst	B	Light purple, eye clean to slight imperfections, little or no color zoning, good cut & polish.	E
Amethyst	A	Med/light purple, eye clean to slight imperfections, little or no color zoning, good cut & polish.	E
Amethyst	A+	Med purple, eye clean to slight imperfections, little or no color zoning, good cut.	E
Amethyst	AA	Med dark to dark purple, eye clean to slight imperfections, little or no color zoning, good cut.	E
Amethyst	AAA	Deep purple, eye clean to slight imperfections, little or no color zoning, good cut.	E
Aquamarine	B	Included, light color, good cut.	H
Aquamarine	A	Slightly included, medium to light color, good cut.	H
Aquamarine	AA	Eye clean, medium color, good cut.	H
Aquamarine	AAA	Eye clean, medium to dark color, good cut.	H
Bloodstone	Very Good	Dark green with red to brownish spots, medium dome cabochon.	N
Cameo	Very Good	Shell carving, white face on orange to brown background, facing left or right.	N
Carnelian	Very Good	Orange red to brownish orange, medium dome cabochon.	D
Chalcedony	Very Good	Medium powder blue, translucent to opaque, medium dome cabochon.	N
Chrysoprase	Very Good	Medium bright green, translucent to opaque, medium dome cabochon.	N
Coral	Very Good	Light to medium salmon, “Pink Coral”, good polish, good cut, medium cab.	N
Citrine	A	Clean, yellow, medium to light, good cut, little or no color zoning.	H
Citrine	AA	Eye Clean, gold/goldish orange, med to dark, good cut, little or no color zoning.	H
Citrine (Palmeira)	AAA	Eye Clean, med. golden to yellowish orange, good cut, little or no color zoning.
CZ, Signity Star	Excellent	Internally clean, perfectly machine cut and polished to ideal conditions. D color of diamonds. High grade cz with more colorful flashes of fire than most diamonds.	SYN
Diamond	See 4'cs	Note: for diamond grade information go to Four C's for more information.	N
Diamond Accents	SI/G-H	Slightly included. G to H color. Good cut. See Four C's for more information.	N
Emerald	B	Light color, included (cloudy), good cut, good polish.	E
Emerald	A	Medium color, slightly included, good cut, good polish.	E
Emerald	AA	Medium dark, slightly included, good cut, good polish.	E
Emerald	AAA	Very slightly included, med. dark to dark color, brilliance, good cut and polish.	E
Garnet, Mozambique	AA	Eye clean, medium to dark, red to orange brown, good cut.	N
Garnet, Rhodolite	AA	Eye clean, medium to dark, raspberry to plum, good cut.	N
Garnet, Tsavorite	AA	Eye clean, light forest green, top brilliance, excellent cut and polish.	N
Garnet, Tsavorite	AAA	Eye clean, medium forest green, top brilliance, excellent cut and polish.	N
Garnet, Tsavorite	Gem	Eye clean, dark forest green, top brilliance, excellent cut and polish.	N
Iolite	AA	Med/dark grayish purple, grape color, good cut.	N
Jade	Very Good	Nephrite Jade, apple to green, medium/dark, good polish, good cut, low cab.	N
Lapis	Very Good	Med/dark, some gold flakes (Pyrite), even color, good polish, medium dome.	D
Moonstone	Very Good	Milky, transparent to opaque, medium dome cabochon.	N
Opal	A	White background, med fire, color range – blue & greens, greens or blue reds.	N
Opal, Mexican Fire	Very Good	Medium to dark orange, faceted, good cut.	E
Pearl, Cultured, Mabe	Very Good	White, good luster, good shape.	ASBL
Pearl, White Cultured	A	Very light cream to pinkish white to white, minor blemishes, very good luster.	E
Pearl, Cultured, South Sea	AA	Clean, good shape, good luster, (color range: white, pinkish or cream).	N
Pearl, Black Cultured	AA	Medium gray to black, minor blemishes, very good luster.	D
Pearl, Black Cultured, South Sea	AA	Medium gray to black, minor blemishes, very good luster, near round to round.	N
Pearl, Freshwater	Very Good	Very light cream to pinkish white to white, minor blemishes, very good luster.	E
Pearl, Black Freshwater	Very Good	Varying hues of black, minor blemishes, very good luster.	D
Pearl Strand, Cultured	AA	Very light cream to grayish white, minimal blemishes, high luster.	E
Pearl Strand, Cultured	AA	Very light cream to pinkish white, few blemishes, very good luster.	E
Pearl Strand, Cultured	AA	Very light cream to yellowish white, minimal blemishes, medium luster.	E
Pearl Strand, Freshwater	Very Good	Very light cream to grayish white, minimal blemishes, high luster, spherical shape.	E
Pearl Strand, Freshwater	Very Good	Very light cream to yellowish white, minimal blemishes, high luster, spherical shape.	E
Onyx, Black	Very Good	Black, good polish, good cut.	D
Padparadscha, Lab Created	Gem	Eye clean, very clear, very bright orange, good cut/polish.	SYN
Peridot	AA	Eye clean, medium to dark, slightly yellowish green, good cut.	N
Smoky Quartz	AA	Eye clean, color ranges from medium light (tan) to med dark (brown), good cut.	E
Ruby	B	Included, light pinkish red, good cut, good polish.	H
Ruby	A	Slightly included medium pinkish red, good cut, good polish.	H
Ruby	A+	Eye clean, medium dark pinkish red, good cut, good polish.	H
Ruby	AA	Eye clean, medium dark pinkish red, brilliance, good cut, good polish.	H
Ruby	AAA	Eye clean, medium dark pinkish red to red, brilliance, excellent cut and polish.	H
Sapphire, Blue, Lab Created	Gem	Eye clean, dark navy blue, good cut/polish and brilliance.	SYN
Sapphire, Blue	A	Slightly included, med./dark navy, good cut/polish, brilliance.	H
Sapphire, Blue	A+	Very slightly included, med. navy, brilliance, good cut/polish.	H
Sapphire, Blue	AA	Eye clean, med. navy to royal blue, brilliance, good cut/polish.	H
Sapphire, Blue	AAA	Eye clean, med. navy to royal blue, brilliance, excellent cut/polish.	H
Sapphire, Pink	AA	Eye clean, med pink, brilliance, good cut, polish.	H
Sapphire, Pink	AAA	Eye clean, med to dark pink, brilliance, excellent cut/polish.	H
Sapphire, Pink, Lab Created	Gem	Eye clean, bright clear pink, high brilliant flashy stone, excellent cut/polish.	SYN
Star Sapphire, Blue	AA	Dark blue, patches of white, good star with light, good polish/cut, med dome.	H
Star Sapphire, Black	AA	Charcoal gray/dark brown, good star with light, good polish/cut, med dome.	N
Sapphire, Yellow	AA	Eye clean, medium yellow, brilliance, good cut/polish.	H
Sapphire, Yellow	AA	Eye clean, medium to dark yellow, brilliance, excellent cut/polish.	H
Sapphire, White	AA	Eye clean, near colorless, brilliance, good cut, good polish.	H
Tanzanite	B	Eye clean, light, bluish purple, brilliance, good cut/polish.	H
Tanzanite	A	Eye clean, med light, bluish purple, brilliance, good cut/polish.	H
Tanzanite	A+	Eye clean, med light, bluish purple, brilliance, good cut/polish.	H
Tanzanite	AA	Eye clean, medium bluish purple, good cut, polish & brilliance.	H
Tanzanite	AAA	Clean, med dark, bluish purple, brilliance, good cut/polish.	H
Tanzanite	Gem	Clean, vibrant, med dark, bluish purple, brilliance, good cut/polish.	H
Tanzanite, Lab	Very Good	Clean, vibrant, dark, blue with violet overtones, brilliance, good cut/polish.	SYN
Tiger Eye, Brown	Very Good	Golden brown. good cut/polish, med dome.	E
Tiger Eye, Honey	Very Good	Golden Honey color, good cut/polish, med dome, good eye.	E
Green Topaz	Very Good	Medium bluish green, clean, good cut, polish & brilliance.	U
Glacier Blue Topaz	Very Good	Royal Blue, clean, good cut, polish & brilliance.	U
London Blue Topaz	AA	Med/dark, clean, good cut, polish & brilliance.	R
Pink Topaz	Very Good	Pink to rose, clean, good cut, polish & brilliance.	U
Sky Blue Topaz	AA	Eye clean, bright light blue, good cut.	R
Swiss Blue Topaz	AA	Eye clean, med/dark bright blue, brilliance, good cut/polish.	R
Teal Topaz	Very Good	Eye clean, bluish green, brilliance, good cut/polish.	U
Topaz, Precious	A	Eye clean, light golden color, good cut.	N
Topaz, Precious	AA	Eye clean, medium golden to slight peach, good cut.	N
Topaz, Precious	AAA	Eye clean, medium/strong golden to peach tones, good cut.	N
Topaz, Precious	Imperial	Eye clean, peach to pink color, good cut.	N
Topaz, White	Fine	Signity: Minimal eye visible inclusions, colorless, machine cut.	H
Tourmaline, Green	A	Eye clean, to slightly included, medium to dark yellowish green, good cut.	E
Tourmaline, Green	AA	Eye clean, to slightly included, medium yellowish green, good cut.	E
Tourmaline, Pink	AA	Eye clean, medium color, bright pink, good cut.	E
Turquoise	Very Good	Bright light blue, no matrix, good cut.	N
Blue Zircon	AA	Eye clean, medium/dark, slightly greenish blue, good cut.	H
Alexandrite, lab simulated	Very Good	Eye clean, Violet red with a very slight change to grayish purple, good cut/polish	SYN
Chatham Created Alexandrite	Gem	Eye clean to very minimal eye visible inclusions, medium/dark greenish blue to medium violet red, good cut.	SYN
Chatham Created Emerald	Fine	Minimal eye visible inclusions, medium/dark green, good cut.	SYN
Chatham Created Emerald	Gem	No eye visible inclusions, medium/dark green, good cut.	SYN
Chatham Created Padparadscha	Fine	Minimal eye visible inclusions, medium/light reddish orange (pink), good cut.	SYN
Chatham Created Ruby	Fine	Minimal eye visible inclusions, medium/dark blood red, good cut.	SYN
Chatham Created Ruby	Gem	No eye visible inclusions, medium/dark blood red, good cut.	SYN
Chatham Created Sapphire	Gem	Very minimal eye inclusion, dark to medium blue, good cut.	SYN
Moissanite, White	Very Good	Slightly tinted greenish yellow, good cut, very high dispersion.	SYN
Moissanite, Green	Light	Light mint green crystal material, good cut, very high dispersion.	SYN
Moissanite, Green	Medium	Dark mint green crystal material, good cut, very high dispersion.	SYN
Moissanite, Green	Dark	Vibrant dark green crystal material, good cut, very high dispersion.	SYN

Shipping Continuous United States, Alaska and Hawaii.

Prices in US Dollars subject to change without notice.