Glittering Stones » Gemstone Facts

Gemstone Facts

Every gemstone is distinct in terms of hue, color grades, clarity, hardness, cut, tone and saturation. To understand the difference, several parameters are used by GIA (Gemological Institute of America) to distinguish between gemstones. GIA reports represent the highest standard of reliability, consistency and integrity.

Precious & Semi Precious Gemstone Facts

Amethyst

Diamond

Garnet

Sapphire

GIA Color Grade Scale

Abbreviation	Hue	Abbreviation	Hue
P	Purple	styG	strongly yellowish-Green
rP	reddish-Purple	yG	yellowish-Green
RP/PR	Red-Purple or Purple-Red	slyG	slightly yellowish-Green
stpR	strongly purplish-Red	G	Green

More About GIA Color Grade Scale

GIA Tone And Saturation Scale

GIA Tone Scale

0	1	2	3	4
Colorless or White	Extremely Light	Very Light	Light	Medium-Light

GIA Saturation Scale

1	2	3	4	5	6
Brownish or Grayish	slightly Brownish or slightly Grayish	very slightly Brownish or very slightly Grayish	Moderately Strong	Strong	Vivid

More About Gem Tone and Saturation Scale

Colorless Gem Grading Scale

Color	GIA	CIBJO
Colorless	D	Exceptional white+
	E	Exceptional white
	F	Rare white+
Near Colorless	G	Rare white
	H	White
	I	Very slightly tinted white
	J	Slightly tinted white

More About Colorless Gem Grading Scale

GIA Clarity Grades

Type I Clarity Scale

Exceptional	Very Good	Good	Fair	Poor
VVS	VS	SI	I1... I2	I3
Very Very Slightly Included	Very Slightly Included	Slightly Included	Included	Excessively Included

More About GIA Clarity Grade Scale

Type I Clarity Scale

Type II Clarity Scale

Type III Clarity Scale

Gem Hardness

MOH's Hardness	Mineral used for comparison	Simple Hardness	Cutting Hardness (A. Rosiwal)
10	Diamond		140,000.00
9	Ruby , Sapphire , Alexandrite , Chrysoberyl		1,000.00
8	Aquamarine , Emerald , Morganite , Spinel , Topaz		175.00
7	Amethyst , Citrine , Garnet , Iolite, Kunzite , Peridot , Tanzanite , Tourmaline , Zircon	Scratches window glass	120.00

Learn More About Gem Hardness

Gem Cut

Brilliant Full Cut

Eight Cut

Rose

Half Dutch Rose

Learn More About Gem Cut

NOVEMBER BIRTHSTONE - CITRINE

COMMEMORATIVE EVENT - 13th Anniversary
KEYWORDS - Success, Abundance, Personal Power
ALSO KNOWN AS - Merchant's stone, Success stone
COLORS - Pale yellow to brown
OCCURRENCE - Brazil
COLOR ZONING - Tiger stripes or Zebra stripes