Abstract: A gemstone rating system is provided particularly for rating the cut of diamonds in which particular cuts and features are measured and the results compared with and provided with a predetermined score depending upon deviations from a theoretical perfect cut; and wherein the deviation scores are summed and then subtracted from an initially perfect score to provide a universally comparable indication of quality of cut.

Abstract: A gemstone rating system is provided particularly for rating the cut of diamonds in which particular cuts and features are measured and the results compared with and provided with a predetermined score depending upon deviations from a theoretical perfect cut; and wherein the deviation scores are summed and then subtracted from an initially perfect score to provide a universally comparable indication of quality of cut.

Abstract: The invention relates to internal combustion engines and provides for the use of a piston cylinder within which a piston slidably reciprocates. A piston rod is pivotally attached at one of its ends to the piston and at its second end to a connector arm which is mounted for pivotal movement below the piston cylinder. A connecting rod is carried by the connector arm to rotate a crankshaft about an axis which is spaced from the pivotal axis of the connector arm. The connecting rod is secured to the connecting arm a distance from the piston rod to transmit the rotational movement to the crankshaft. When the piston moves from a top dead center position to a bottom dead center position, the crankshaft rotates by more than one half of a full revolution, thereby increasing efficiency of the engine.