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Need help on evaluating 2 diamonds

Discussion in 'RockyTalky' started by confused, Nov 30, 2001.

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  1. confused
    Rough_Rock

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    Nov 30, 2001
    by confused » Nov 30, 2001
    I am considering two different diamonds and am uncertain which is a better deal. I ran the Holloway Cut Advisor on both and the lower clarity stone rated better, but the vendor I am working with has discounted the HCA. I would appreciate some feedback on which stone you would consider to be the best stone. The difference in price between the two is $400. The primary differences appear to be the Clarity, Crown/paviliion angles and the HCA rating. On-line pricing tools suggest that Diamond 1 while slightly smaller should be at least $4000 more expensive due to the higher clarity. I am curious as to which you would recommend and why? If the HCA had not been so much better on Diamond 2 it would have been an easy choice.

    Diamond 1 - HCA 2.3

    2.48 ct F VVS1
    Depth 61.1
    Table 55
    8.8-8.77-5.37
    AGS-0
    Cut ideal
    Polish ideal
    Symmetry ideal
    Flouresence none
    Girdle .7-1.3
    Culet Pointed
    Crown angle 34.6 degree
    Pavillion angle 41 degree

    Diamond 2 - HCA .7

    2.56 F VS1
    Depth 61.7
    Table 55.3
    8.77-8.8-5.42
    GIA cert
    Polish VG
    Symmetry VG
    Flouresence None
    1% Culet
    Crown angle 34 degree
    Pavillion angle 40.4 degree
    Girdle .7
     
    


    


  2. pricescope
    Ideal_Rock

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    by pricescope » Nov 30, 2001
    Diamond price obviously isn't based on HCA score. HCA is just a tool to filter light leaking diamonds.

    Diamond #1 with pavilion angle 41 degree has a partial light leakage under the table. These areas will appear pale in ideal scope. HCA penalizes this. However, 2.3 is still very good score so it is a nice stone.

    Diamond #2 with shallower pavilion shouldn't have any major light leakage and hence it has better HCA score.

    I would say that both stones should be very nice and ideally you should look at both and choose the one you like the most.

    As for average prices in the price stat tool, it seems doesn't give the right picture in this case. It takes diamonds from 2 to 2.99 carat and gives you average per carat price. There could and should be fluctuations from the averages.

    Interestingly enough, Rapaport Diamond Report™ also gives $2,700 per carat difference for VVS1 and VS1 in this carat range

    Without taking HCA into account, #1 looks like a better deal because of the clarity. As for the cut, I suggest you should see and compare both diamonds to tell which one you like the most or examine the cut quality with an expert.
     
  3. Garry H (Cut Nut)
    Super_Ideal_Rock
    Trade

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    14,541
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    by Garry H (Cut Nut) » Nov 30, 2001
    Stone #2 does not exist - those parameters are wrong. This stone must have an extremely thick girdle or those crown and pavilion angles are very very wrong.
    Where did they come from?
    Garry Holloway
     
  4. pricescope
    Ideal_Rock

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    by pricescope » Dec 1, 2001
    You're right Garry and good point!

    I also was surprise #2 has deeper total depth than #1. It cannot have shallower crown and pavilion then unless girdle is very thick. Confused, you might want to double check it.

    I would guess they both were/are listed in the web. I'm I correct?
     
    


    


  5. confused
    Rough_Rock

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    Nov 30, 2001
    by confused » Dec 1, 2001
    Gary,

    I am having trouble attaching the sarin report and cert. The cert is as described in the first posting. The sarin report is difficult to read but I will give you everything I can make out:

    Diameter 8.8 (8.78-8.82)
    Depth 5.43 (61.1%)
    Crown 34 degree (15.5%) (0)
    Pavillion 40.4 degree (42.5%) (0)
    Table 4.87m (55.3%) (0)
    Culet 1% v. small (0)
    Girdle .7-1.5% (1.1%)(0)
    Symmetry very good

    Thanks for your help!! I found your tutorial very informative. One of the best I've seen, which is why I was giving it so much weight in my initial analysis.
     
  6. pricescope
    Ideal_Rock

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    by pricescope » Dec 1, 2001
    ----------------
    On 12/1/2001 10:48:02 AM

    Gary,

    I am having trouble attaching the sarin report and cert. The cert is as described in the first posting. The sarin report is difficult to read but I will give you everything I can make out:

    Diameter 8.8 (8.78-8.82)
    Depth 5.43 (61.1%)
    Crown 34 degree (15.5%) (0)
    Pavillion 40.4 degree (42.5%) (0)
    Table 4.87m (55.3%) (0)
    Culet 1% v. small (0)
    Girdle .7-1.5% (1.1%)(0)
    Symmetry very good

    Thanks for your help!! I found your tutorial very informative. One of the best I've seen, which is why I was giving it so much weight in my initial analysis.
    ----------------



    While Garry is :snore: ...

    5.43mm depth is 61.7% from 8.8mm (not 61.1%). It is too much for these pavilion and crown: 15.5% + 42.5% = 58% i.e. almost 4% difference with total depth...:-o
     
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