📏 Beyond the 4 Cs – Diamond Length-to-Width Ratio

How to Choose the Perfect Shape & Proportion for Maximum Beauty

💎 What Is Length-to-Width Ratio?

When it comes to fancy-shaped diamonds (anything that isn’t round), length-to-width ratio (L/W) is the hidden gem of diamond proportions.

It tells you how elongated or square a diamond appears, calculated by dividing the diamond’s length by its width.

📐 Length ÷ Width = L/W Ratio
e.g. A diamond that’s 7.5mm long and 5mm wide = 1.5 ratio → elegant and elongated

✨ Why It Matters

• Looks on the finger – certain ratios flatter different hand and finger shapes
• Overall style – vintage, bold, modern, or delicate
• Visually balanced version of each shape
• Square, classic, or elongated appearance

📊 Ideal Length-to-Width Ratios by Shape

💡 The ideal range depends on personal style—some prefer more square, others more elongated. It’s about balance and visual flow.

👁️‍🗨️ How L/W Ratio Affects Appearance

🔷 Elongated Ratios (Higher Numbers)

• Create the illusion of longer fingers
• Look graceful and vintage-inspired
• Ideal for: Oval, Emerald, Marquise, Pear

🔶 Squarer Ratios (Lower Numbers)

• Appear chunkier or more balanced
• Look modern, bold, or compact
• Ideal for: Princess, Asscher, Round, Cushion

💍 Which Ratio Works for You?

🧠 FAQs – L/W Ratio Demystified

✅ Pros & Cons of Prioritising L/W Ratio

✅ Pros:

• Helps personalise your choice to hand shape
• Improves aesthetic balance of the diamond
• Creates variety within one shape category (e.g. cushion or oval)

⚠️ Cons:

• Often overlooked by new buyers
• Doesn’t guarantee sparkle (cut quality is still king)
• Higher ratios may affect how a stone fits in standard settings

Tip to Mitigate: Always view the diamond on your hand or finger shape—or request a visual mock-up to compare proportions before purchase.

🧾 Final Tip: Don’t Just Choose the Shape – Choose the Right Version of It

Two oval diamonds can look completely different depending on their length-to-width ratio. By understanding this subtle measurement, you can:

• Pick the shape that best suits your finger
• Find the balance between sparkle and spread
• Personalise your ring to suit your unique aesthetic

Beyond the 4 Cs, it’s these hidden proportions that make your diamond truly yours. 💍

Martin Commins

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