Holloway Cut Advisor (HCA): PART 1
The ABC's of HCA SCORE!
HCA is the short abbreviation for The
Holloway Cut Advisor (U.S. Patent 7,251,619), invented by Garry Holloway. The HCA
is used to estimate a round diamond’s appeal based on its potential Light
Return, Fire, Scintillation and Spread, in other words, to estimate the
effectiveness of light return from a diamond’s cut. This tool is wonderful not
just because it can estimate a diamond’s appeal but because it is also a free! :) (http://www.pricescope.com/tools/hca)
The HCA is designed to aid a novice
consumer or an experienced trade buyer in selecting diamonds they have not seen.
To get a diamond’s HCA score, you need to input the figures for Total Depth %,
Table %, the diamond’s Crown degree angle/% and Pavilion degree angle/%.
It is best to input Crown and Pavilion
angles than percentages because percentages are often rounded; for example, a
13.3% can be rounded off to 13%. Likewise, some certificates list less accurate
rounded Crown percentages and Pavilion percentages, therefore if you want to be
sure that the diamond has excellent light return, you may ask the vendor to get
you a Helium, Sarin or Ogi report to give you better accuracy with the
specifications of the diamond.
After inputting the diamond
specifications in the formulae provided, you will receive a HCA Score. A score under
2 (Excellent) means you have eliminated known poor performers, which is more
than 95% of all diamonds. Most people prefer diamonds that rate 1-2 on the
scale where: 0-2 Excellent, 2-4 Very Good, 4-6 Good, 6-8 Fair, and 8-10 Poor.
Zero is almost impossible because of conflicting factors; your personal
preference may be for a diamond with an HCA score of 1.5 than one with a lower HCA
score of 0.5.
The Ideal range of diamonds is 1% of the
worlds’ diamond supply and here at JANNPAUL, all diamonds go through a
stringent process of filtration. To ensure and maintain this standard of
quality to customers, we only accept and stock diamonds with a HCA score of 1.4 and below, which is equivalent to
less than 0.01% of the worlds’ diamond supply.
Although the HCA is wonderful for calculating
the effectiveness of light return in a diamond, we must stress that there are
limitations to the HCA as well. Keep an eye out for our next entry, where we
will describe the limitations of the HCA and why it should only be used as an elimination tool and not solely as a quality
measurement.
Find out your score today!
