Unless otherwise stated, all gemstones are graded and evaluated in their mountings to the maximum extent that the mounting permits examination. Approximate weights are formulated by taking measurements and applying acceptable formulas; as such they are estimates only. Keen determination of color, clarity and proportions may be prevented by certain types of mountings, small fancy, round, full and single, and baguette cut diamonds (melee) are evaluated according to their approximate weights and average quality grades using Gemological Association of Great Britain (Gem-A) grading scale.
Major diamonds are graded with the use of pre-graded permanent master diamonds color comparison stones and the grading nomenclature prescribed by the Gem-A. Colored Gemstones are graded using the Gem-A prescribed colored stones grading system and nomenclature. Major colored stones are described using Gem Dialogue color grading system. Because mountings prohibit full and accurate observation of gem quality and weight, all data pertaining to mounted gems can be considered as approximate unless accompanied by an independent laboratory certificate (AGL, EGL, Gem-A).
Unless otherwise stated, all stones and pearls are assumed to be subject to a relatively stable and possibly undetected color or clarity enhancement. Authenticity, antiquity, decorative periods, vintages and or circa dating are determined to the best of our ability based on materials incorporated, methods of manufacture, design, hallmarks & signatures, lapidary techniques, technological developments and consultation of our extensive reference library and materials. Dating and period attributions are not an exact science as decorative periods frequently overlap and borrow influences from one another.