top of page
sparkling diamonds of every different cut and shape  on a white sparkling background .jpg

Gemstone Guide

northgeorgiadiamon

 


Birthstones


 

Do you Know the Birthstones?
Do you Know the Birthstones?

 

"Modern" column: Birthstones listed are the Official Birthstone adopted by the American National Association of Jewelers, Jewelers of America. These Birthstones were officially adopted in 1912."Traditional" column: Contains older birthstones and is sometimes combined with the modern birthstone list. (Many jewelers have differing lists of Traditional Birthstones.)


 


 

"Alternate" column: Contains stones used by Gem Dealers and Jewelry Manufacturers as alternate birthstones for each month.




Month

Color

Modern

Traditional

Alternate

January

Brick Red

Garnet

Garnet

Rose Quartz

February

Purple

Amethyst

Amethyst

Black Onyz Moonstone

March

Seafoam Blue

Aquamarine

Bloodstone

Rock Crystal

April

Colorless

Diamond

Diamond

White Sapphire White Topaz

May

Green

Emerald

Emerald

Green Tourmaline Tsavorite Garnet

June

White

Pearl/Moonstone

Alexandrite

Opal

July

Red

Ruby

Ruby

Rubellite Tourmaline

August

Yellowish-Green

Peridot

Jade

Star Sapphire

September

Royal Blue

Blue Sapphire

Blue Sapphire

Iolite Lapis Lazuli

October

Pink

Opal Pink Tourmaline

Jasper

Pink Sapphire Moganite

November

Golden Yellow

Golden Topaz Yellow Citrine

Yellow Citrine

Yellow Sapphire Tiger's Eye

December

Sky Blue

Blue Topaz or Turquoise

Blue Zircon Turquoise

Blue Spinel Lapis Lazuli



Anniversary Gemstones



This list of suggested gemstone gifts is endorsed by the American Gem Trade Association, the American Gem Society, Jewelers of America, The Jewelry Industry Council, the Gemological Institute of America, and the Cultured Pearl Association of America.



Year

Gemstone

Year

Gemstone

1st

Gold Jewelry

2nd

Garnet

3rd

Pearls

4th

Blue Topaz

5th

Blue Sapphire

6th

Amethyst

7th

Onyx

8th

Green Tourmaline

9th

Lapis Lazuli

10th

Diamond Jewelry

11th

Turquoise

12th

Jade

13th

Yellow Citrine

14th

Opal

15th

Ruby

16th

Peridot

17th

Watches

18th

Cat's Eye Chrysoberyl

19th

Aquamarine

20th

Emerald

21st

Iolite

22nd

Spinel

23rd

Imperial Topaz

24th

Tanzanite

25th

Silver Jubilee

30th

Pearl Jubilee

35th

Emerald

40th

Ruby

45th

Sapphire

50th

Golden Jubilee

55th

Alexandrite

60th

Diamond Jubilee

70th

Sapphire Jubilee

80th

Ruby Jubilee



Relative and Absolute Hardness Scale


In 1812 the MOH's scale of gem hardness was devised by German mineralogist Frederich Mohs (1773-1839). MOH's hardness is a relative scale. It shows which mineral scratches another mineral. The table below shows MOH's hardness in relation to Simple and Cutting Hardness. (Cutting hardness in water according to A. Rosiwal).


MOH's Hardness

Mineral used for Comparison

Simple Hardness Tester

Cutting Hardness (A. Rosiwal)

10

Diamond

 

140,000.00

9

Corundum

 

1,000.00

8

Topaz

 

175.00

7

Quartz

Scratches window glass

120.00

6

Orthoclase Feldspar

Can be scratched with a steel file

37.00

5

Apatite

Can be scratched with a knife

6.50

4

Fluorite

Can be easily scratched with a knife

5.00

3

Calcite

Can be scratched with a copper coin

4.50

2

Gypsum

Can be scratched with a fingernail

1.25

1

Talc

Can be scratched with a fingernail

0.03



GIA Color Grades



Color Explanation of Colored Gemstones: The GIA "Color Stone Grading System" is made up of three main components, Hue, Tone and Saturation.


Hue is described as the shade, tint or sensation of a color: The GIA Gem Set has 31 Hues which can be used to describe virtually all colored gemstones. The complete GIA Gem Set includes 324 sample hue colors with varying Tones and Saturations.


Tone is described as the strength or purity of a Hue. The GIA Tone Scale is divided into 11 grades, 0 to 10, with 0 being colorless to 10 being black.


Saturation is described as the strength or purity of a Hue. The GIA Saturation Scale is from 1 to 6. The lower numbers such as 1, 2, or 3 of warm colors such as red, orange or yellow and tend to look brownish and the cool colors such as blue and green tend to look grayish. Level 4 no longer shows either grayness or brownness , while neither is strong or weak. Level 5 is strong and Level 6 being vivid, almost over colored.



11 views0 comments

Recent Posts

See All

How to clean Jewelry

Education - Jewelry Care JEWELRY CAREAt North Georgia Diamond, we provide you with a Jewelry Care Guide that will help your jewelry...

How to Buy A Diamond

Education - The 4 C's Of Buying A Diamond THE 4 C's OF BUYING A DIAMOND Planning to buy a diamond? We, at North Georgia Diamond,...

Comments


© 2035 by ROCHETTE. Powered and secured by Wix

bottom of page