Diamond Measurements and Machinery

Hearts & Arrows

Diamond Measurements and Machinery

Today Sarin and Ogi instruments are used to read and analyze measurements, angles and percentages. This is not a method to indicate the perfection of cutting. These machines show the perfection of the engineering in the equipment and the maintenance of the equipment.

Today's cutting equipment is a lot more exacting. What is more important is that the equipment is in good condition and that the cutting plate skyf (pronounced skife like knife) and tang (tool to hold the diamond) are true and level (Fig. 1b) with each other so that there is very little deviation in the measurements when the stone is completed. The larger the stone the more visible this deviation can possibly be.

Note in Fig. 1a that the cutter can dial in the angle for the main pavilion or crown angles for the process of blocking out the stone in 8 cut. As you can see this is not entirely up to the cutter but also the engineers from the maintenance dept.

The precision of the cutter is really seen in the brillanteering (polishing on the lower and upper girdle facets as well as the stars) of the stone. This is where the craft comes into today's diamond cutting world, the finishing of the stone the upper and lower girdle facets (half's) and the stars. It is here where we have to rely entirely on the cutter for his mastery.

The Sarin and Megascopes are not measuring all these other angles at present, but the precision an consistency of these angles would reveal how great the cutter is. One method which reveals this all is by looking through the H&A scope at the hearts, one can see the precision and consistency of the cutting.

The antithesis of this is when a master diamond cutter swindles a stone, meaning he recovers the maximum possible weight and makes a lively stone. The angles; measurements and percentages will deviate by much on this stone, compared to a superideal. The Sarin machine will not show this mastery in the cutting but deviation yes. This machinery dose not prove how perfectly the stone has been cut. There is still one simple method above all the sophisticated MACHINERY and that’s the heart and arrow scope. If the machinery were to measure no deviation in other words if each angle was exactly the same one would view a diamond that would look dull to the eye much like a tympani drum, if one plays it in the center the sound is not good at all compared to when it is beat off to the side.

Conclusion ť

Figure 1a

Figure 1b

Figure 1c