The OpenFacet Diamond Composite Index (DCX) is a transparent benchmark that tracks per-carat retail prices for natural GIA-certified round diamonds with 3EX grading (cut, polish, symmetry) and no fluorescence. It focuses on high-liquidity segments, smoothing per-carat price data across color and clarity grades within fixed carat bands.

DCX serves as a diamond price index, derived from structured retail inventory snapshots and processed using log-linear and geometric interpolation techniques. This ensures consistency, interpretability, and responsiveness to market dynamics, while filtering out anomalies and unavailable specs. The DCX is updated regularly and is designed for integration into diamond pricing engines, retail quoting tools, and market analysis dashboards.

DCX supports valuation workflows, algorithmic pricing, market tracking, and synthetic asset modeling. For full methodology and construction details, see the About OpenFacet & DCX Methodology page.

Disclaimer: The Diamond Composite Index (DCX) is a model-based benchmark constructed from public retail listings. It does not represent executable prices or financial advice. All data is filtered, interpolated, and smoothed for index use. Use at your own discretion. GIA is a registered trademark of the Gemological Institute of America. This site is not affiliated with, endorsed by, or associated with GIA.