Checkerboard

Checkerboard crowns stretch facets into squares across the table, yielding bold sparkle even on shallow stones. This layout is popular for colored gems that rely on saturation rather than brilliance.

Design Highlights

• Square outline with evenly spaced crown facets to create the grid effect.
• Flatter crown to keep the table broad while still offering relief cuts.
• Pavilion angles tuned shallow to keep depth low for weight retention.

FSL Spec

Note: the design below is adapted from the "GemCad Advanced Tutorial". This is not an easy one, but the idea is to create points in a 4x4 grid, project one after another on the facet above and cut a new tier. The angles are optimized for quartz.

The surface() helper makes this much easier by projecting grid points directly onto the stone.

name = "GemCad Advanced Tutorial NEW"
ri = 1.54
gear = 64

// Simpler version with the surface() function 

G1 3 @ 90.00 : 0.9500 xx4
C1 1 @ 54.983 +/- 2 : cp()

midp1 = ep(edge(C1:1, G1:61), 0.5)
midp2 = ep(edge(C1:31, G1:35), 0.5)

G2 1 @ 90.00 : midp1
ur = mp(C1, { index: 40, angle: 90 })
ll = mp(C1, { index: 10, angle: 90 })

C2 3 : midp1 
     : surface(3/4, 1/4, ll, ur)
C3 8 : gp({ index: 6 })
     : surface(3/4, 0/4, ll, ur)
C4 3 : surface(3/4, 1/4, ll, ur)
     : surface(4/4, 1/4, ll, ur)
C5 8 : surface(2/4, 1/4, ll, ur)
     : surface(3/4, 1/4, ll, ur)

P1 1 @ 45.3667 +/- 2 : mp(C1) + -girdle
P2 3 @ 44.193 +/- 2 : gp()
P3 2 @ 44.596 +/- 2 : gp()