|The Simplicity Oval|
|Copyright 2/96 by J. Rowland|
|Angles for R.I. = 1.54||79 facets + 16 facets on girdle = 95|
|2-fold, mirror-image symmetry||96 index|
|L/W = 1.267 T/W = 0.947 T/L = 0.747||P/W = 0.450 C/W = 0.129|
|H/W = (P+C)/W+0.02 = 0.599||P/H = 0.752 C/H = 0.215|
|Vol./W^3 = 0.283|
|g1||90.00||20-28-68-76||CAM Preform 34.2 degrees|
|g2||90.00||13-35-61-83||CAM Preform 36.3 degrees|
|g3||90.00||08-40-56-88||CAM Preform 38.3 degrees|
|g4||90.00||02-46-50-94||CAM Preform 40 degrees|
|c0||42.00||96-48||Cut to form narrow keel|
|b1||45.00||02-46-50-94||Cut to g4-c0 meet|
|c1||42.00||03-45-51-93||Cut to b1-b2-girdle meet|
|c2||42.00||07-41-55-89||Cut to b1-b2-girdle meet|
|c3||42.00||09-39-57-87||Cut to b2-b3 girdle meet|
|c4||42.00||12-36-60-84||Cut to b2-b3-girdle meet|
|c5||42.00||14-34-62-82||Cut to b3-b4 girdle meet|
|c6||42.00||19-29-67-77||Cut to b3-b4 girdle meet|
|B1||45.00||08-40-56-88||Leave some girdle|
|M1||35.00||04-44-52-92||Cut to B1-B4 girdle meet|
|M2||35.00||12-36-60-84||Cut to B1-B2 girdle meet|
|M3||35.00||17-31-65-79||Cut to B2-B3 girdle meet|
|S1||25.00||04-44-52-92||Cut to M1-B4 and M2-B1 meets|
|S2||25.00||12-36-60-84||Cut to M1-M2-S1-B1 meet|
|B2||38.00||13-35-61-83||Recut to 38 degrees and M2-M2-S2 meet|
|T||00.00||Table||Cut to S2-M3 meets at ends|
|The oval is shaped via CAM Preform settings given with each girdle setting. These should meet at a center point. The girdle is leveled from these settings to form the oval shape. These facets will be cut away.|
I've called this design Simplicity because for an oval it is fairly easy to cut. My design goal was to develope a meetpoint oval that required no guesswork and had a very limited number of angle settings. I wanted an unusual looking crown with no dark spots anywhere in the stone. It also needed to sparkle like all get-out and show no "bow tie" typical of most ovals. Simplicity fits the bill.
I would classify Simplicity as an intermediate project, not because it is hard to cut, but because it has a large number of facets. As long as care is taken in cutting the pre-form and hitting the meetpoints accurately you should have no trouble cutting this stone.
Start by making the CAM Preform. Use the girdle index settings and the angles supplied and cut to a common center point. Now level the girdle on these index settings to get your oval shape. The CAM facets will be cut away later.
The c0 facets are cut to form a narrow keel. Be sure it is wide enough, we don't want a point, we want a keel. All the pavilion meet points meet at the girdle. Don't worry that there are no meets elsewhere. Believe me, meet points do not make a gem sparkle! Most of my designs get their sparkle from the mix of crown and pavilion facets. I try not to "stack" my facets. This allows a single crown facet to cross several pavilion facets breaking light up all over the place!
On the crown the B2 facet is cut first at 45 degrees to get a level girdle to provide a meetpoint target later on. B2 is later recut to 38 degrees.
I don't think there is any size too big for this cut, but due to the large number of facets, I wouldn't try it on a small stone under 10 mm in length. Please let me know what you think of Simplicity. It doesn't look simple when it is finished!
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