The simple answer is, yes, particularly if you’re basing the value on the grade from a reputable diamond grading agency such as the GIA or EGL.
The GIA and EGL are the primary diamond grading agencies. They impartially grade stones based on the four c's cut, color, clarity, and carat weight. The GIA and EGL grade both vintage and new stones using the same standards. If a diamond is certified with I color and VS1 clarity, the value is established regardless of its age.
Up until about ten years ago, old cut diamonds such as old mine cushion and old European, were viewed by many as diamonds that needed to be recut into modern cuts like the brilliant cut. A diamond dealer would often devalue the stones by approximately 20-30 percent as that would be the amount of diamond weight lost in the recut.
As time went on and the demand for antique diamonds increased, so too has the price. Today we are seeing comparable prices of new and old cut diamonds. In some cases old cut stones have surpassed in price.
There is an increased interest in old diamonds for a number of reasons. First, they are becoming increasingly rare. Second, antique stones are an easy way to avoid controversial conflict diamonds, not to mention they are also earth friendly! And lastly, the big, brilliant, blingy jewels popular during the last few decades are becoming passé. More delicate, subtle, and understated gems are gaining popularity, not only because of their history, but also because of their rich brilliance and textured sparkle.
We love antique stones and prefer them to the big and brilliant modern stones. We choose to set our own collection By Erstwhile with only antique stones.