Idealscope

[kbaker]

Can you use an idealscope when the stone is mounted or just on a loose stone? Just wondering! I have a family heirloom and I would love to check it out with the idealscope

 

[pricescope]

Here is the link how to use Ideal-Scope on mounted stones: http://ideal-scope.com/using_mounted_diamonds.asp

 

[denverappraiser]

A few comments on using the IS for mounted stones:

It’s important that the stone be viewed from a position perpendicular to the table. Tilting like is done in the picture on the left causes a very different perspective. You can do a decent job of this by lining up the culet with the center of the table reflection. This assumes that there are no symmetry problems with either the culet or the table but you can generally spot these with a loupe before you start. If you have lots of light, you can also get some clues to the leveling by looking for the glare off of the table but this does take some practice.

Centering matters.

Cleanliness matters. The optics of dirty diamonds are quite a bit different from the same diamond if it’s clean.

Optimally, the girdle plane should be at the opening of pink cone. If it’s too close or too far away you will get a very different look. If you mounting will accommodate this, try placing the stone table down on a flat surface and pick it up in your tweezers by the girdle of the stone. Touch the edge of the cone with both sides of the tweezers about half an inch from the stone. This has the effect of leveling and centering at the same time although it doesn’t work with all mountings. This gets easier with a bit of practice and with a good pair of tweezers.

Keep your fingers out of the way.

Keep both eyes open while you practice or it gives you a headache.

It works best to have quite a bit of light from a source that is centered directly behind the piece. The sky works pretty well but obviously you shouldn’t be looking directly at the sun. Standard ceiling lights are pretty good too but a lot of have really icky color.

Remember that the mounting is blocking off at least some of your transmitted light and that this may have a significant effect on what you see. Be careful about the conclusions you make, especially with regard to leakage. Some mountings will block almost all of the transmitted light while others block very little.

Neil Beaty
GG(GIA) ISA NAJA
Independent Appraisals in Denver

 

[Regular Guy]

Date: 7/20/2005 2:24:02 PM
Author: denverappraiser
It’s important that the stone be viewed from a position perpendicular to the table. Tilting like is done in the picture on the left causes a very different perspective. You can do a decent job of this by lining up the culet with the center of the table reflection. This assumes that there are no symmetry problems with either the culet or the table but you can generally spot these with a loupe before you start. If you have lots of light, you can also get some clues to the leveling by looking for the glare off of the table but this does take some practice.

Neil,

Interesting, but it seems counter-intuitive.

You look at it sideways? This is 90% different then when not mounted, right?

Do you want to say anything about the principles regarding what you''re doing with this technique?

Regards,

 

[denverappraiser]

Ira,

No no no. It's the same view as with an unmounted stone. It's just that with mounted stones its easy to end up with a considerable tilt unless you make a point to avoid it. In the center of the pavilion is a reflection of the table and by centering the culet in this reflection you end up with decent leveling.

neil

 

[kbaker]

Wow Neil,
Thanks for the great feedback. I knew that I could use the idealscope, but wasn''t sure that it would be reliable, especially at the hands of a novice. I appreciate your time!

 

[denverappraiser]

If this image were taken unmounted, you would see quite a bit more white around the outside edges. The unevenness of the arrows at the 7 o'clock position is due to the leveling. The dark black shafts on the arrows and the extra parts at 10 and 5 o'clock are because it's being held to far into the cone. The unequal black triangles between the arrowheads (do these have a name?) is because it's not well centered and off of level.

Notice how the table reflection, the culet and the table are not lined up very well. The stone is tilted slightly towards the 2 o'clock direction.

All in all, this is a crummy picture of a pretty good stone. If this stone were imaged by one of the experts unmounted you would see none of these problems. When you're handholding both the stone and the tool and onlyl looking for a few seconds, there are quite a few areas where errors can creep in and this needs to be taken into consideration when you draw your conclusions.

Neil Beaty
GG(GIA) ISA NAJA
Independent Appraisals in Denver

 

[denverappraiser]

Here''s another one. These photos are out of my photo reject stash so I don''t actually know much about the stones other than what''s in the picture. This one has a pretty bad tilt towards the 6 o''clock direction and it''s quite dirty.

 

[denverappraiser]

On more, just so you guys can play.

What do you guys think of either the picture or the stone?

Neil Beaty
GG(GIA) ISA NAJA
Independent Appraisals in Denver

 

[kenny]

Deep