How much does 1 carat of a pre-owned diamond cost?

What is the Value of a Pre-Owned Diamond?

Whether you're looking to sell a diamond or purchase a "second-hand" one, it's essential to understand how the value of a pre-owned diamond is estimated. The pricing of used diamonds differs from that of new ones. In this article, we will explore the factors that determine their value and explain why selling might still be advantageous, regardless of the price.

Factors Affecting Diamond Prices: The 4Cs

Until the mid-20th century, there were no universal criteria for evaluating diamonds. Today, diamonds are evaluated worldwide based on the so-called 4Cs.

• Carat (Weight): The unit of measurement used to indicate a diamond's weight. One carat equals 0.2 grams.
• Color: A diamond is primarily made of crystallized carbon. Most natural diamonds either have no color or display varying shades of yellow. However, the presence of other atoms within the diamond's structure can cause variations in color. Diamonds may have shades of brown, blue, green, pink, orange, or purple. Red diamonds are extremely rare.
• Clarity: For a diamond to be considered absolutely pure, it must be free from any blemishes or inclusions. Clarity is assessed by observing the stone under ten magnifications.
• Cut: The cut of the diamond—whether round, heart-shaped, oval, marquise, or pear—is one of its most important features as it determines how the stone radiates brilliance.

Other factors affecting the final cost of a diamond include polishing, symmetry, fluorescence, and shape.

Market Trends

In addition to the 4Cs, the price of a diamond is influenced by market trends, which are impacted by various factors such as the global economy, fashion trends, geopolitics, and innovations in the production sector. Historically, the diamond market has always been volatile, but in recent years, the trend has been notably declining. This is primarily due to:

• The impact of the pandemic.
• Ethical concerns surrounding mining practices.
• The growing presence of synthetic diamonds in the market.

Synthetic diamonds, offering a more affordable and sustainable alternative to natural diamonds, have become increasingly popular, particularly among younger consumers.

Average Diamond Price

Once the characteristics of a diamond are established, its price is typically determined based on the Rapaport Diamond Report, commonly referred to as the Rapaport. The Rapaport serves as the "price list" for diamonds, published every Friday and available exclusively to industry professionals. Prices are listed in US dollars, with diamonds categorized by weight, color, and clarity, while the cut is not factored in.

Below is a table published by Stonealgo, updated as of January 19, 2025, showcasing the price of a 1-carat diamond in the most common cuts. The last column reflects the price change compared to the previous month.

The most costly diamond cuts are those that maximize light reflection, thereby enhancing the diamond’s brilliance. Fashion also plays a significant role in price fluctuations: round cuts are the most commonly chosen for engagement rings, while pear-shaped cuts are often featured in high-end jewelry collections.

New vs. Pre-Owned: What Drives Price Differences?

The prices listed in the table refer exclusively to new diamonds. Generally, the price of a 1-carat pre-owned diamond ranges from one-third to one-sixth of its original retail price. Pre-owned diamonds are typically priced significantly lower than new ones, regardless of the cut.

However, determining the value of pre-owned diamonds solely by carat weight would be an oversimplification: the price can vary considerably based on factors such as clarity and color. Additionally, it's essential to consider the preservation of the diamond's value: over time, it is highly likely that a diamond’s value may decrease.

What Determines the Value of a Pre-Owned Diamond?

In conclusion, the criteria for evaluating pre-owned diamonds are similar to those for new ones, yet pre-owned diamonds are more vulnerable to market fluctuations. While a diamond piece purchased from a jeweler is often valued based on design, brand, and setting, a pre-owned diamond is primarily assessed based on the characteristics of the diamond itself. Given the current market trend, it is highly likely that the value of pre-owned diamonds will continue to decrease in the coming years.

If you have decided to sell your pre-owned diamond, it is essential to consult with industry experts who can properly assess its value, considering all of its attributes, rather than focusing solely on carat weight.

For a free, comprehensive valuation, reach out to Auctentic, where our experts will not only provide an accurate price but also explain the various factors that influence its value.