The Hayek Cut For Gemstones

The Hayek cut was named after the Nobel Laureate economist F. A. Hayek. Although this design was developed to fit a specific piece of beryl rough, the cut can be very useful for faceting other kinds of gems, too. Any time you have a blocky piece of rough that is not square enough for an emerald cut, try the Hayek.

Hayek cut - Beryl
Beryl Gemstone with Hayek Cut

This beauty has a Barion style pavilion, which accounts for its great brilliance. The optical performance of this cut is outstanding in light to medium colored rough. However, I would caution against using the Hayek cut in darker rough.

This is a fairly simple design to cut. Now that you have it in your repertoire, you should find multiple uses for this diagram.

The Hayek Cut: Diagrams

The Hayek Cut: Instructions

  • Angles for R.I. = 1.56
  • 45 facets + 4 facets on girdle = 49
  • 96 index
  • L/W = 1.500 T/W = 1.066 T/L = 0.710
  • P/W = 0.807 C/W = 0.110
  • H/W = (P+C)/W+0.02 = 0.937
  • P/H = 0.862 C/H = 0.117
  • Vol./W^3 = 0.628

Pavilion

Step Angle Index Notes
1 43º 96-06-12-18-24-30-36-4248-54-60-66-72-78-84-90 Cut to temp center point (TCP)
2 90º 44-92 Meet with step 3 at edge from step 1
3 90º 24-72 See step 2
4 75.5º 24-72 Meet at 1-2-3
5 75.5º 44-92 Meet at 1-2-3
6 42º 09-57 Add the mains last
7 41.5º 45-93
8 41.4º 33-81
9 41º 21-69

Crown

Step Angle Index Notes
a 42º 04-52 Steps a to f meet at corners
b 42º 24-72
c 30.7º 25-73
d 31.5º 23-71
e 32.2º 05-53
f 31.4º 03-51
g 25º 04-52 Meet e-a-f
h 22.1º 24-72 Meet c-d-b
T 0º Table Meet h-d-e-g and g-f-c-h