What Is the Difference Between 14ct and 18ct Gold?

In a world where many retailers simply resell mass-produced items, TJ Gold & Diamond stands as a powerhouse of true creation. As one of the largest vertically integrated jewellery manufacturing companies, we don't just sell jewellery—we build it. From our state-of-the-art facilities to your doorstep, here is a behind-the-scenes look at how we master the art of manufacturing from A to Z, and why choosing a direct-to-consumer manufacturer is the smartest move for your next masterpiece. https://www.tjdiamond.co/en-nz/pages/manufacturing-process 1. Concept and 3D CAD Design Everything begins with a vision. Whether it’s a rough sketch or a detailed dream, our expert designers use high-end Computer-Aided Design (CAD) software to create a digital blueprint. This allows us to perfect the proportions and show you a photorealistic preview of your piece before a single grain of gold is melted. 2. High-Precision Resin Printing Once the digital model is perfected, we move into the physical world. Using advanced 3D resin printers, we create a high-resolution wax-like model. This ensures that the intricate details—the fine filigree and the precise stone seats—are captured with a level of accuracy that hand-carving simply cannot match. 3. The Casting House: From Wax to Gold This is where the magic happens. We operate our own casting house, allowing us to control the purity and quality of our alloys. Using the "lost wax" casting method, the resin model is encased in a flask, burned out, and replaced with molten 14k, 18k, or platinum. By refining our own metal, we guarantee the integrity of every gram. 4. Our Specialized Chain Factory One of the capabilities that truly sets TJ Gold & Diamond apart is our dedicated chain manufacturing factory. While most jewellers buy their chains from a third party, we manufacture our own. From classic links to complex designs, having this in-house ensures a level of durability and finish that is second to none. 5. Master Setting and Hand-Finishing Once the raw casting is complete, it moves to our master jewellers. Our stone setters use microscopic precision to secure each diamond and gemstone. Following the setting, the piece goes through a multi-stage polishing and finishing process. We don't stop until the metal has a mirror-like luster that reflects our high standards. 6. The Chemical Edge: In-House Rhodium & Refining Our expertise extends even to the chemistry of the trade. We manage our own refining and chemical production, including our own rhodium plating solutions. This vertical integration means we know exactly what goes into every layer of your jewellery, ensuring a brilliant, long-lasting white-gold finish that doesn't fade prematurely. 7. Strict Quality Control (QC) & Dispatch Before any piece leaves our facility for New Zealand, Houston, or beyond, it undergoes a rigorous multi-point QC check. We inspect the stone security, the prong integrity, and the overall finish. Only when it is perfect is it dispatched to our retail showroom or shipped directly to you. Why You’re Making the Right Choice When you choose TJ Gold & Diamond, you are cutting out the middleman. You aren't paying for a "brand markup"—you are paying for expertise, raw materials, and craftsmanship. Direct to Consumer: By manufacturing everything in-house, we pass the savings directly to you. Global Reach, Local Touch: With operations in NZ and Houston, we combine global manufacturing power with personalized service. Unmatched Capability: From CAD design to chemical refining, there is no part of the process we don't master. Ready to start your journey? Experience the confidence that comes with buying directly from the source. At TJ Gold & Diamond, if you can dream it, we can manufacture it. https://www.tjdiamond.co/en-nz/pages/manufacturing-process

Quick guide: Want the focus on the diamond? Solitaire. Want maximum visual impact per dollar? Halo. Want the most durable and practical setting? Bezel. Want extra diamond presence without a halo? Three-stone. Want a sparkling band? Pavé. Want architectural drama? Split-shank or cathedral. The setting of an engagement ring determines how the diamond sits on the band, how it is secured, and how much of the diamond is visible. It is the second most important decision after the diamond itself, and it affects both the visual character and the practical durability of the ring. This guide covers every major setting style with the specific advantages and the buyer profile each setting suits best. Solitaire Settings Browse solitaire engagement rings. A single diamond, a plain band, no additional accent stones. The solitaire is the most classic engagement ring configuration and the one that puts every aspect of the centre diamond's quality and character on full display. The four-prong solitaire is the most common and creates a rounder visual profile around the stone. The six-prong solitaire provides more security and creates a crown-like profile that suits round and oval centres particularly well. Best for: Buyers who want the centre diamond to be the complete focus of the ring. Buyers who want maximum compatibility with any wedding band. Buyers prioritising a larger centre stone within their budget. Consider if: You want a minimal, timeless aesthetic without decorative elements on the band or around the stone. Halo Settings Browse halo engagement rings. A ring of smaller accent diamonds surrounds the centre stone, amplifying the perceived size by approximately 0.25 to 0.50 carats. A 0.80 carat centre in a halo reads comparably to a 1.25 to 1.30 carat solitaire. The hidden halo (accent diamonds set slightly below the centre stone) reads as a solitaire from above with additional depth and sparkle visible at close range. Best for: Buyers who want maximum visual impression within their budget. Cushion, oval, pear, and heart shaped centres, where the halo follows the distinctive outline of the shape. Consider if: You want more overall sparkle and diamond presence than a solitaire, or if your centre stone budget is modest and you want to maximise face-up appearance. Bezel Settings Browse bezel engagement rings. A rim of metal encircles the entire perimeter of the diamond, holding it flush within the band. The bezel is the most secure setting, as the metal rim protects the stone's edge all the way around. No prongs to catch on clothing or fabrics. Particularly suited to active lifestyles and buyers who use their hands in physical work. Best for: Active lifestyles where prongs would be a practical inconvenience. Buyers who prefer a sleek, modern, architectural aesthetic. Round, oval, and emerald centres where the clean outline reads clearly within the metal frame. Consider if: Security and low-maintenance wearability are higher priorities than maximum light exposure to the stone. Pavé Settings Small accent diamonds set closely together along the band with minimal metal between them, creating a continuously sparkling surface. Pavé adds sparkle and visual weight to the ring without competing with the centre stone. Full pavé runs diamonds on all sides of the band. Half-pavé runs diamonds on the visible top half only. Micro-pavé uses smaller stones for a finer, more delicate texture. Best for: Buyers who want more overall sparkle than a plain solitaire without adding a halo. Buyers who want the band to contribute visually to the ring rather than recede. Consider if: You want a plain band to pair cleanly with the wedding band — pavé bands can limit compatible wedding band styles. Three-Stone Settings Browse three-stone engagement rings. A centre diamond flanked by two matching or complementary side stones, traditionally representing the past, present, and future. Side stones can match the centre shape (oval centre with oval sides) or contrast it (oval centre with pear sides pointing inward, emerald centre with baguette sides). Three-stone settings add more diamond presence than a solitaire without adding a halo. Best for: Buyers who want more diamond presence without a halo. Buyers who want a design with symbolic meaning built into the structure. Oval, cushion, and emerald centres pair particularly well with contrasting side stone shapes. Consider if: You want a design that feels more distinctive and custom than a standard solitaire or halo. Split-Shank and Cathedral Settings A split-shank setting divides the band into two separate strands as it approaches the centre stone, adding architectural drama. A cathedral setting arches the metal sides upward, raising the centre stone above the plane of the band for maximum visibility and a dramatic side profile. Both add complexity and visual interest to the setting without adding accent diamonds. Best for: Buyers who want architectural drama and a distinctive band profile. Round, oval, and cushion centres, where the raised or split frame creates a strong visual contrast. Consider if: You have an active lifestyle — raised or complex band profiles can catch on surfaces more than a low-profile bezel or plain solitaire. Choosing Between a Solitaire and a Halo — The Practical Decision This is the most common setting decision buyers face. The practical framework: Choose a solitaire if your priority is a larger, higher-quality centre stone and you want all visual attention on the diamond's own character. Choose a halo if your priority is maximum visual impression at a given total budget, and you are comfortable with a ring that is more decorative in character. Choose a hidden halo if you want the maximum visual impact of a halo with the clean top profile of a solitaire — the hidden halo reads as a solitaire from above and as a halo from the side. There is no objectively correct setting. The solitaire and the halo represent two different philosophies about what an engagement ring should be. Both are equally appropriate. The decision is entirely personal. Browse our full engagement ring collection to see all setting styles across all diamond shapes and metals. Or  contact us to discuss which setting style suits your specific diamond shape, budget, and lifestyle. Frequently Asked Questions Q1: What is a solitaire engagement ring setting? A solitaire setting features a single centre diamond on a plain or simply detailed band, with no additional accent diamonds on the setting or band itself. The solitaire is the most classic and most widely recognised engagement ring configuration. Its defining advantage is simplicity: all visual attention goes to the centre diamond, whose quality, size, and character are fully visible from every angle. A solitaire setting suits any diamond shape and any metal. The most common solitaire variations are the four-prong (which creates a more circular diamond outline) and the six-prong (which creates more security and a crown-like profile). Solitaires are also the easiest setting to resize and the most compatible with any wedding band style, whether plain, pavé, or contoured. Q2: What is a halo engagement ring setting? A halo setting surrounds the centre diamond with a ring of smaller accent diamonds, amplifying the perceived size of the centre stone by approximately 0.25 to 0.50 carats and adding sparkle density to the overall ring. A 0.80 carat centre diamond in a halo typically reads comparably to a 1.25 carat solitaire. The halo is the most popular setting style for oval and cushion cut centres in the current market. A standard halo sits at the same plane as the centre stone; a hidden halo (also called a floating halo) is set slightly below the centre stone, creating the appearance of a solitaire from above with additional sparkle visible from the side and at close range. Halo settings pair particularly well with oval, cushion, pear, and heart shaped centres, where the halo follows the distinctive outline of the shape. Q3: What is a bezel engagement ring setting? A bezel setting encircles the entire perimeter of the centre diamond with a rim of metal, holding the stone flush within the band. The bezel is the most secure of all common settings, as the metal rim fully protects the diamond's edge all the way around. It is the most practical setting for active lifestyles, as there are no prongs to catch on clothing or fabrics. The bezel produces a sleek, modern, clean profile that suits contemporary and minimalist aesthetics particularly well. It also suits round, oval, and emerald cut centres most naturally, where the clean outline of the shape reads clearly within the metal frame. The bezel's protective quality makes it particularly recommended for softer precious stones and for buyers who use their hands frequently in physical work. Q4: What is a pavé engagement ring setting? A pavé setting (from the French word for paved) features small accent diamonds set closely together along the band with minimal metal between them, creating a continuous, sparkling surface that appears paved with diamonds. The diamonds are held by tiny metal beads or prongs, producing the characteristic glittering band that is one of the most popular engagement ring band styles. Pavé bands add sparkle and visual weight to the ring without adding a halo or competing with the centre stone. A full pavé band runs diamonds on all sides of the band. A half-pavé runs diamonds only on the visible top half. A micro-pavé uses smaller diamonds for a finer, more delicate texture. Pavé settings require careful maintenance as the small prongs holding each stone can wear over time with daily use. Q5: What is a three-stone engagement ring setting? A three-stone setting features a centre diamond flanked by two matching or complementary side stones. The three stones traditionally represent the past, present, and future of a relationship. The side stones may be smaller versions of the same shape as the centre (round centre with round sides, oval centre with oval sides), or contrasting shapes that complement the centre outline (oval centre with pear sides pointing inward, emerald centre with baguette sides). Three-stone settings are particularly popular for oval, cushion, and emerald centres. They add more diamond presence than a solitaire without adding a halo. Three-stone rings with contrasting side stone shapes tend to read as more distinctive and custom in character than matching sets. Q6: What is a split-shank or cathedral engagement ring setting? A split-shank setting features a band that divides into two separate strands as it approaches the centre stone, creating a dramatic frame for the diamond and adding visual interest to the band's profile. The split shank creates a sense of openness and architectural detail that a plain band does not. A cathedral setting raises the centre diamond above the plane of the band by arching the metal sides upward to hold the stone at a higher position, increasing the diamond's visibility and the dramatic effect of the ring's profile from the side. Both split-shank and cathedral settings suit round, oval, and cushion centres particularly well. They are generally not recommended for buyers with active lifestyles where the raised or complex band profile might catch on surfaces. Q7: Should I choose a solitaire or a halo engagement ring? Choose a solitaire if you want the focus entirely on the centre diamond's quality and character, prefer a cleaner and more minimal profile, want maximum compatibility with any wedding band style, or are prioritising a larger centre stone within your budget. Choose a halo if you want to maximise the visual impression of the centre stone at a given budget (the halo adds approximately 0.25 to 0.50 carats of perceived size), prefer a more dramatic and decorative ring profile, or are choosing a cushion, oval, pear, or heart shaped centre where the halo follows the distinctive shape outline. The halo also suits buyers who prefer more diamond presence overall. Both settings are equally appropriate for any occasion or lifestyle. The most practical deciding factor is whether you want maximum budget in the centre stone (solitaire) or maximum overall visual impression (halo). Q8: What is the most popular engagement ring setting in NZ? The solitaire remains the most popular engagement ring setting in New Zealand overall, accounting for the majority of engagement ring sales by style. The oval solitaire in 18ct yellow gold is currently TJ Diamond's most-requested configuration in New Zealand and the broader international market. Halo settings are the second most popular, particularly for cushion and oval centres. The hidden halo has seen strong growth in the NZ market since 2022. Bezel settings have grown steadily as buyers seek more minimalist aesthetics and practical durability. Three-stone settings remain popular for milestone occasions and for buyers who want more diamond presence without a halo. Pavé bands are the most popular band style addition to solitaire settings across all shapes and metals.  

Both are independent, reputable certification labs. GIA applies slightly stricter standards for natural diamonds and is the most widely trusted globally. IGI is the standard certifier for lab-grown diamonds. TJ Diamond stocks both GIA and IGI certified stones and recommends GIA for natural diamonds and IGI for lab-grown. When you buy a diamond engagement ring, the certificate that accompanies it is your primary independent quality verification. Every diamond TJ Diamond sells carries either a GIA (Gemological Institute of America) or IGI (International Gemological Institute) certificate. This article explains what each certifier is, how their standards differ, and how to choose between them. What GIA and IGI Both Do Both GIA and IGI are independent gemological laboratories — they do not buy or sell diamonds. Their role is to assess the quality of diamonds submitted to them and issue a grading report documenting the four quality variables (cut, colour, clarity, and carat weight) to a defined standard. Neither lab has a financial interest in the grade the diamond receives. Both laboratories are accepted by jewellers, insurance companies, and diamond dealers globally. A GIA or IGI certificate accompanies the ring and can be used for insurance valuation, resale documentation, and independent quality verification. Both labs also provide online report verification tools where any buyer can confirm the certificate's authenticity by entering the report number. The Key Differences Factor GIA IGI Founded 1931 — oldest major diamond lab 1975 — largest by volume Grading standards More conservative, slightly stricter in middle grades Slightly less conservative in middle grades — same scale Natural diamond reputation Highest in the industry Well-respected, slightly below GIA for natural stones Lab-grown diamonds Certifies lab-grown, less common Industry standard for lab-grown diamonds Resale value (natural) Highest — GIA commands a premium Slightly below GIA on secondary market Resale value (lab-grown) Equivalent to IGI Equivalent to GIA for lab-grown Price per certificate Higher — premium for strict standards Lower — more accessible pricing Online verification gia.edu/report-check igi.org/verify Why GIA Is Preferred for Natural Diamonds GIA applies slightly stricter grading standards than IGI in the middle quality ranges (F-J colour, VS1-SI1 clarity). This means a GIA G VS2 natural diamond has been verified against a stricter standard than an IGI G VS2. In practice, two diamonds with identical certificate grades from different labs may not be identical stones. A GIA-graded stone at a given grade is more reliably within the stated grade range than an IGI-graded stone at the same grade. For natural diamonds where long-term resale value is a consideration, GIA is the preferred certificate. The secondary market for natural diamonds applies a modest premium to GIA-certified stones, particularly at the 1 carat and above level. GIA certificates are also the most universally accepted by US jewellers for trade-in or upgrade programs. Why IGI Is the Standard for Lab-Grown Diamonds The majority of lab-grown diamonds are IGI-certified, and IGI's lab-grown grading standards are well-established. GIA also certifies lab-grown diamonds, but GIA lab-grown certificates are less common in the market simply because most lab-grown diamond producers have standardised on IGI. Both are entirely appropriate for lab-grown diamond certification — the choice between them for lab-grown is less significant than for natural diamonds. Browse TJ Diamond's full selection of lab-grown diamonds — all available with IGI or GIA certification at equivalent quality grades to natural diamonds. What a Certificate Does Not Tell You A certificate documents grades — it does not show you what the stone looks like. Two diamonds with identical GIA grades can appear meaningfully different in person due to differences in specific facet arrangement within the grade range, inclusion placement (a cloud near the table vs an inclusion near the girdle), fluorescence character, and the individual proportions within the stated depth and table ranges. This is why TJ Diamond provides virtual consultations for every diamond: the certificate tells you what the grades are, and the consultation shows you what the stone actually looks like. For a complete explanation of what the 4Cs mean and how each affects a diamond's appearance, see our article what are the 4Cs of diamonds?. For an understanding of how certificate grades affect diamond pricing, see how much does a 1 carat diamond ring cost?. Browse our full engagement ring collection, or  contact us to ask about specific GIA or IGI certified stones and arrange a virtual consultation. Frequently Asked Questions Q1: What is the difference between GIA and IGI diamond certification? GIA (Gemological Institute of America) and IGI (International Gemological Institute) are both independent diamond grading laboratories that issue certificates documenting a diamond's cut, colour, clarity, and carat weight. GIA is the older and more established of the two, founded in 1931, and its grading standards are widely considered the most conservative and consistent in the industry. IGI was founded in 1975 and is the world's largest independent gem certification and appraisal institute by volume. Both certificates are accepted by insurance companies and jewellers globally. The primary differences: GIA applies slightly stricter grading standards than IGI in the middle quality ranges, and GIA certificates command a modest premium in the natural diamond resale market. For lab-grown diamonds, IGI is the more widely used certifier and their grading is well-regarded. Q2: Which certificate is better for an engagement ring, GIA or IGI? For natural diamonds, GIA is the more conservative and widely respected certification. A GIA-certified natural diamond with a given colour and clarity grade is typically graded to a slightly stricter standard than an IGI-certified diamond at the same grade, meaning a GIA G VS2 and an IGI G VS2 may not be identical stones even at the same certificate grades. For lab-grown diamonds, IGI has become the industry standard. The majority of lab-grown diamonds are IGI-certified, and IGI's lab-grown grading is well-established and widely accepted. TJ Diamond offers both GIA and IGI certified diamonds. For natural diamonds where long-term resale value is a consideration, GIA is generally preferred. For lab-grown diamonds, IGI is the standard choice and entirely appropriate. Q3: Does a GIA or IGI certificate guarantee diamond quality? A GIA or IGI certificate documents the diamond's measured grades at the time of grading — it is an objective record, not a guarantee of subjective quality. Two diamonds can carry identical GIA grades and appear meaningfully different in person due to differences in facet pattern, fluorescence character, inclusion placement (a cloud near the table vs an inclusion near the girdle), and the specific proportions within the grade range. The certificate provides the essential quality framework for comparison, but it does not replace in-person or virtual visual assessment. This is why TJ Diamond holds virtual consultations for every diamond before purchase — the certificate tells the buyer what the grades are, and the consultation shows the buyer what the stone actually looks like in the specific setting metal they have chosen. Q4: Is IGI trustworthy for lab-grown diamonds? Yes. IGI is the most widely used certifying laboratory for lab-grown diamonds and their lab-grown grading standards are well-established and consistently applied. The majority of lab-grown diamonds produced by leading growers are IGI-certified, and IGI certificates for lab-grown diamonds are accepted by jewellers, insurance companies, and resellers globally. GIA also certifies lab-grown diamonds and their grading is equally respected, though GIA lab-grown certificates are less common in the market. Both GIA and IGI lab-grown certificates use the same 4Cs grading framework as natural diamond certificates, with the addition of a notation indicating the diamond is laboratory-grown. Q5: Can you tell if a diamond is lab-grown from its GIA or IGI certificate? Yes. GIA and IGI certificates for lab-grown diamonds state explicitly on the certificate that the diamond is laboratory-grown, using wording such as "laboratory-grown," "lab-grown," or "synthetic" depending on the certifier and the year of certification. The certificate also typically notes the growth method (CVD or HPHT). A natural diamond certificate will not contain any such notation. The diamond's unique report number can be verified on the GIA or IGI online lookup tool, where the same information is visible. A buyer receiving a diamond with a certificate can therefore verify the natural or lab-grown status of any GIA or IGI certified stone independently and immediately. Q6: What does the GIA grading scale for diamond colour mean? The GIA colour grading scale for white diamonds runs from D (completely colourless) to Z (light yellow or brown). D, E, and F are colourless grades, visible as colourless to the naked eye in any setting. G, H, I, and J are near-colourless — appearing colourless to the naked eye in most settings, with slight warmth visible under magnification or in direct comparison with a D-F stone. K through Z show increasing visible warmth or yellow tint. For most engagement ring buyers, G or H colour represents the practical sweet spot: effectively colourless in the finished ring at a meaningfully lower price than D-F grades. The colour grade advantage of warm metal settings (yellow gold, rose gold) allows buyers to select H or I colour without visible warmth, saving significantly at any carat weight. Q7: How do I verify a GIA or IGI diamond certificate is genuine? Every GIA and IGI certificate carries a unique report number printed on the certificate. For GIA certificates, enter the report number at gia.edu/report-check to verify the certificate's authenticity and view the graded details. For IGI certificates, enter the report number at igi.org/verify to verify. The online record will confirm the same grades shown on the physical certificate. Most modern GIA and IGI certified diamonds also have the report number laser-inscribed on the girdle of the diamond itself (the narrow band around the edge), which can be verified under 10x magnification by any trained jeweller. TJ Diamond provides the specific certificate report number before any purchase is finalised, so buyers can independently verify the stone's grades before the ring ships. Q8: Do natural diamonds hold their value better than lab-grown diamonds? Natural diamonds have historically retained value better than lab-grown diamonds on the secondary market. Lab-grown diamond prices have declined significantly since 2020 as production technology has improved and production volumes have increased, reducing the price premium that early lab-grown diamonds commanded. As of 2025, lab-grown diamonds at retail are typically 50-70% below natural equivalents at the same quality grades. On resale, the gap is typically even larger. For buyers whose primary goal is a visually impressive ring within a defined budget, lab-grown provides the most stone presence per dollar. For buyers who specifically want a ring that holds secondary market value, natural diamonds remain the more conservative choice. TJ Diamond offers both natural and lab-grown diamonds with GIA and IGI certification, allowing buyers to make an informed choice based on their specific priorities.