Zoning

[megeve]

Is this zoning what I see at 3 o''clock? Does zoning has a negative effect on stones? Can someone please explain? Thank You!

 

[LD]

Megeve I''m definitely not an expert but that looks like inclusions at 3 o''clock rather than colour zoning. Zoning tends to look like darker areas of colour fading to lighter areas. I found this great picture on the web that shows it very clearly although this is a severe case and the photo looks enhanced but it gives you a general idea!

 

[megeve]

Oh, thanks LD! Is that how zoning looks like? My, so the one I posted is inclusion, are they needles then?

Back to zoning, from what I see in your sample pic, zoning affects the coloring of the stone? making the color lighter?

 

[LD]

Rather than making the stone lighter, zoning is sort of like stripes of darker areas within the stone. Terrible description but that''s the only way I can describe it. Does that make sense? Ignore the lighter area in the picture I posted - concentrate on the stripes you can see. That''s zoning.

I''m really not an expert on inclusions but those do look like needle inclusions. Hopefully somebody will chime in to help more.

 

[T L]

LD is correct. Zoning are concentrations of color in "zones" throughout a stone, and it's typically unwanted unless it's a bi-color stone. Amethysts and sapphires are prone to zoning.

 

[Stone Hunter]

That second photo shows zoning. I think of it as the color not being the same all the way thru the stone. Like a cup of hot chocolate that didn''t get stirred enough for the chocolate to be evenly throughout the drink.

HTH

 

[chrono]

Date: 11/15/2009 9:38:24 PM
Author: Stone Hunter
That second photo shows zoning. I think of it as the color not being the same all the way thru the stone. Like a cup of hot chocolate that didn''t get stirred enough for the chocolate to be evenly throughout the drink.

HTH

What an excellent clear example of colour zoning. The 1st picture is not zoning; just some inclusions showing at 3 o''clock.

 

[movie zombie]

zoning can also occur as it does in Australian sapphires as a band of a different color. i recently purchased a blue aussie sapphire with zoning but the cutter was able to place the green zoning on the underside of the stone...the only way you know its there is turn the stone upside down.

mz

 

[cushioncutnut]

Zoning always reminded me of a darker "Windex" type streak within the stone..................

 

[Stone Hunter]

Date: 11/16/2009 9:58:42 AM
Author: Chrono

Date: 11/15/2009 9:38:24 PM
Author: Stone Hunter
That second photo shows zoning. I think of it as the color not being the same all the way thru the stone. Like a cup of hot chocolate that didn''t get stirred enough for the chocolate to be evenly throughout the drink.

HTH

What an excellent clear example of colour zoning. The 1st picture is not zoning; just some inclusions showing at 3 o''clock.

Thanks Chrono, you are a Stone Master and I am still a beginner.

I don''t know if the Aussie Sapphires would be considered color zoning since the colors are different, yellow and blue or green and blue. I''ve read that those are called Parti Sapphires. Perhaps a fancy name for some nice color zoning? I think that they look nice.

 

[movie zombie]

for me parti-colored is more of the effect one gets with parti-colored tourmaline. both terms are used here:

http://www.aussiesapphire.com.au/index.php?main_page=index&cPath=3_18&sort=20a&page=2

however, i think parti- is a good description for some of the stones and for others zoning is a good description. i definitely see a difference in the instances in which zoning is mentioned.

here''s a parti-tourmaline:
http://www.africagems.com/pacoto6ca.html

but many think this is a good description of look lzoning:
http://www.jfrankgolden.com/PDF/tourmaline.pdf

symantics in the color world....sign.

mz

ps my aussie sapphire is not parti- at all....its all blue except for a green zone that the cutter did NOT want to show face up to distract from the otherwise absolute blue of the stone. personally, i like some of those "parti-" aussie sapphires as a good one has the colors all mixed up within it. however, if it appears to be a streak of green in an otherwise blue stone, well, for me that''s zoning [the faceter called it that too]. again, its all symantics...... i also think that "parti-" is a more marketable label than "zoning"......

 

[Largosmom]

Thanks so much for posting that photo of color zoning...that is definitely what I was seeing in some of the "better" stones I was shown as candidates for my e-ring...windex streaking is very descriptive too!

 

[Stone Hunter]

Date: 11/16/2009 9:52:22 PM
Author: movie zombie
for me parti-colored is more of the effect one gets with parti-colored tourmaline. both terms are used here:

http://www.aussiesapphire.com.au/index.php?main_page=index&cPath=3_18&sort=20a&page=2

however, i think parti- is a good description for some of the stones and for others zoning is a good description. i definitely see a difference in the instances in which zoning is mentioned.

here''s a parti-tourmaline:
http://www.africagems.com/pacoto6ca.html

but many think this is a good description of look lzoning:
http://www.jfrankgolden.com/PDF/tourmaline.pdf

symantics in the color world....sign.

mz

ps my aussie sapphire is not parti- at all....its all blue except for a green zone that the cutter did NOT want to show face up to distract from the otherwise absolute blue of the stone. personally, i like some of those ''parti-'' aussie sapphires as a good one has the colors all mixed up within it. however, if it appears to be a streak of green in an otherwise blue stone, well, for me that''s zoning [the faceter called it that too]. again, its all symantics...... i also think that ''parti-'' is a more marketable label than ''zoning''......

I like the ones that are described as PARTI better than the ones that mention zoning. Seems that in the PARTI stones the colors are swirled more consistently. Thanks for all of the links!!

 

[RockHugger]

Ditto to all the descriptions above. Is that an ebay tanzie? If so, I think I know who is selling that (The picture technique and the stone type), and I have ordered one from that person in the past. They sell more included stones for a cheaper price. I cant tell you how my stone turned out as I never recieved it...but I got my moneys back quick.
As for the inclusion, it looks like a feather inclusion comming from the side of the stone. Like you are looking down at the side of the inclusion. I had a couple stones that looked like that. If you dont mind a little inclusion (like me) then its a nice stone!