As the financial system risks escalate,an increasing number of investors are turn-ing their attention to alternative assets as a means of value storage.Diamonds,characterized by their scarcity,durability,and portability,are viewed as commodities with investment po-tential.To elucidate the investment potential of colourless diamonds for investors,this study examines the risk-return characteristics of colourless diamonds in the auction market from 2009 to 2022.Varying performance was observed among different qualities of colourless dia-monds,with high-quality ones yielding the poorest returns,indicating they were not a favora-ble investment option during the studied period.Conversely,medium-quality colourless diamonds outperformed bonds and precious metals during the same period,making them a viable addition to investment portfolios.Furthermore,this study employs hedonic regression analysis to explore fac-tors influencing the prices of colourless diamonds in the auction market.Notably,the"4Cs"grading system and association with luxury brands significantly impact colourless diamond prices,with the model explaining over 95%of price variations.Lastly,a correlation analysis between other invest-ment assets and colourless diamonds in the auction market reveals no significant correlation,demon-strating that incorporating colourless diamonds into portfolios can offer diversification benefits and mitigate risk.