Adequate sampling for grading melee diamond batches

Le "Relevant Melee Sampling" appliqué au diamant mêlé

Melee diamond batches are graded (clarity, colour, symmetry, proportions, etc.) on the basis of rigorous sampling. GGTL Laboratories offers RMS (Relevant Melee Sampling), a method for calculating the optimal sample size based on the Cochran formula (1977) with a finite population correction factor. This mathematically grounded approach controls the variability of the sampling process far more effectively than AQL tables, whose use outside a defined procedure generates unacceptable error margins in the context of melee grading.

 

Ressources

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References

  • Cochran, W.G. (1977). Sampling Techniques (3rd ed.). John Wiley & Sons.
  • David, F.G. (2014). Business Statistics: A Decision-Making Approach. Pearson.
  • Evans, J.R. & Lindsay, W.M. (2002). The Management and Control of Quality (5th ed., pp. 115–128). South-Western, Cincinnati.
  • Montgomery, D.C. (2009). Introduction to Statistical Quality Control (6th ed.). John Wiley & Sons.
  • Pires, A.P. (1997). Échantillonnage et recherche qualitative : essai théorique et méthodologique. In La recherche qualitative. Enjeux épistémologiques et méthodologiques (pp. 113–169).
  • Norme ISO 2859-1 (1999). Règles d'échantillonnage pour les contrôles par attributs.