Coloured stones Preliminary Exam

Preliminary examination

A 1st examination to determine

the identity of the stone: naturality, treatment and/or geographical origin if possible.

Features

  • N° 00000
    SPECIMEN

    • Unique number

    The Laboratoire Français de Gemmologie gives a unique number to each deposit. This number identifies the object at each stage of analysis. When a stone has already been viewed and reexamined following a recut or a preliminary examination, it is given a new number.

  • Paris, xx/xx/xxxx

    • Date

    The date corresponds to the end of the analyses and the day on which the report is published.

  • Object
  • Loose stone

    • Object

    The object specifies whether we have received a single stone, a batch or a jewel, and the type of jewel.

  • Identification
  • SAPHIR (NATURAL CORUNDUM)
  • Geographic Origin
  • Sri Lanka (Ceylon)
  • Shape – Cut
  • Oval - Brillant / Step cut

    • Shape – Cut

    The shape, cut and dimensions describe the external appearance of the stone. When you deposit a jewel with several stones, or batches, we note the diametrical variation of the batch.

  • Measurements
  • 12.16 x 9.85 x 6.15 mm

    • Measurements

    The shape, size and dimensions describe the external appearance of the stone. When you deposit a jewel with several stones, or batches, we note the diametrical variation of the batch.

  • Mass
  • 13.19 ct

    • Mass

    The weight of the stones is indicated in carats (1ct = 0.2 g) to two decimal places.

    Rounding is done according to the 3rd decimal place: if it is less than 9 then no rounding, if it is equal to 9 then round up. For example: 0.9990 ct is 1.00 carat but 0.9989 ct is 0.99 carat.

    In the case of jewellery set with stones, it is weighed in grams to two decimal places. The rounding rule that applies is the arithmetic rounding.

  • Opacity
  • Transparent
  • Comment(s)

  • None