The chain measures about 18 and 1/8 inches long, from end to end, and will fit, closed, at just over approximately 18 inches in length. The chain is approximately 1.5 millimeters, or just under about 1/16 of an inch, wide. Stamped on an inline lozenge, "925", and signed with what appears to be an "OGCA" maker's mark. Stamped, "925", again on the spring ring clasp.
The pendant, as it hangs at an angle, measures approximately 11/16 of an inch, or about 17.4625 millimeters, high and wide, and just under roughly about 3/16 of an inch, or approximately 4.7 millimeters. The gemstone setting measures just under about 1/4 of an inch, or approximately 6 millimeters, across. (Included is a US Quarter in the photographs, for the measurement-challenged and ruler-averse.)
Combined weight is approximately 2.67 grams, which includes the stone weight, of course.
This necklace is in very good vintage condition, with no kinks or bends. There will be the expected light surface scratches and possibly some tiny dings to the silver from normal wear. No visible damage to the stone. Hand polished, but it may need further attention. The spring ring clasp works well and holds securely.
A very lovely, modern but feminine, signed Sterling silver open heart pendant necklace with a sparkling, pretty pink gem.