Jewellery Manufacturing Machinery in India

What can you buy here?

Six lines of equipment, plus the parts that keep them running. Melting, casting, rolling, wire drawing and laser equipment are supplied on enquiry rather than listed here.

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Where does each machine fit on the line?

Every unit runs the same broad sequence, whether it makes studded gold for export in SEEPZ or bulk silver in Rajkot.

A wax or metal model is prepared. Stones are set — in wax before casting, or in metal after it. The piece is melted and cast. Sheet and wire are rolled or drawn where they are needed. Parts are joined or marked by laser. Purity is tested. The piece is cleaned and finished.

Machines change the economics at three points on that line.

• Stone setting is the biggest labour cost in studded work. One automatic wax setting machine does the work of a bench of 10 to 12 skilled setters, run by one operator. It places every stone to within ±0.02 mm, hour after hour — an accuracy no hand can hold across a long run.
• Cleaning decides how the piece looks under a loupe. An ultrasonic cleaner lifts polishing compound, wax and plating residue out of pavé and the insides of chain, without anything touching the metal. It also decides how fast QC can move.
• Testing protects the business. XRF reads karat and the full metal mix in 5 to 60 seconds, with no scratching and no acid. It catches gold plating and tungsten-filled bars — the two fakes that acid and density tests miss.

The parts around the setting machine — trays, nozzles, silicone and bases — are where a line actually stops. Downtime in a setting room is almost always a worn nozzle or an empty tub of silicone, not the machine. That is why they are kept in stock in Mumbai and Rajkot: silicone and bases go out the same day, trays and nozzles in about 1 to 2 days.

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Which stone setting machine should you buy?

Two automatic wax setting machines. Both use the same trays, nozzles, silicone and bases. Both hold ±0.02 mm. Both are run from a touchscreen by an operator with no technical background. The difference is how many stations they have, and therefore how much they get through.

Both machines set 99% of the jewellery styles on the market. Neither is the “better” machine — they are built for different volumes.

The honest rule is throughput, not budget

A double station removes the waiting time between batches. That is where the X4 Pro Plus gets its roughly 20% capacity advantage over a conventional setting machine. If you run continuous export orders with fixed shipping dates, or you already have more setting work than one station clears in a shift, it earns the extra floor space.

If you are taking your first step away from manual setting, or you do job work in mixed sizes, the Pro Mini is usually the better buy. It sits on a normal workbench, draws 1.3 kW from an ordinary socket, and an operator learns it in about an hour.

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Which tray and nozzle do you need?

The machine picks each stone off a sorting tray with a nozzle sized to that stone. Using a nozzle outside its size band is the most common cause of dropped stones and failed pickups. Five nozzles and five trays cover round stones from 0.8 mm to 3.0 mm.

All trays take natural diamond, lab-grown diamond (CVD and HPHT), CZ and synthetic rounds. The full pairing logic, including which tray the 503B nozzle belongs with, is on the tray and nozzle selector.

Why the big trays hold fewer stones

Trays for 2.0 mm and up use a deep-pocket grid. A larger stone needs a deeper seat to stay table-up while the arm moves across it, and a stone that tips over is a missed pickup. That is the whole reason capacity drops from 3,200 stones a load to 800 above 2.0 mm. You are buying reliability, not losing capacity by accident.

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What holds the wax model in place?

Two things, and you need both. Silicone does the gripping. The base gives the machine a position it can rely on.

Bases are sold singly and in 1 kg and 2 kg packs. Everything in this section sits under Consumables and dispatches the same day from Mumbai and Rajkot. The full detail is in the wax setting silicone guide.

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What does an ultrasonic cleaner do?

It reaches the places a brush cannot — under prongs, inside chain links, into engraved detail — and it does it without anything touching the metal.

The Semsons Tech ST4820 runs at 40 kHz, the usual frequency for jewellery, in a 2.3 L table-top tank. You start the cycle on a digital display with push-button keys, and a hinged lid with a viewing window lets you watch the pieces in the slotted basket. It is delivered free anywhere in India.

Sizing this properly is worth ten minutes. The tank size guide works it out from your batch, and compares 40 kHz against 28 kHz.

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How do you test gold purity without damaging the piece?

Three ways, depending on what you are testing and where. None of them scratches the piece or uses acid.

• At the counter, gold purity and the full alloy. A benchtop XRF analyzer such as the Signet - PC: the piece goes into a shielded chamber, and X-ray fluorescence reads the gold percentage and the other metals in the alloy.
• Anywhere, the karat. The portable gold testing machine is an electronic tester: the piece lies on a test pad, a pen probe touches the metal, and the screen shows the karat, 0 to 24K. It runs on a rechargeable battery.
• Coins and bars, below the surface. The gold coin testing machine reads electrical conductivity, which finds a tungsten core that a scale and a surface test both miss.
• What they replace. Acid and touchstone testing, which scratch the piece and read only the surface.

Compare them side by side on the gold testing machines page.

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Where does India make jewellery, and what does each hub buy?

About ten manufacturing centres make 75 to 80% of India's jewellery, and each one specialises. Because the equipment a unit needs follows what it makes, the hub you sit in is the sensible place to start.

Semsons Tech has offices in Mumbai and Rajkot. Every other hub is served from Mumbai, with the same installation, training and spares support.

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What comes with every machine?

A machine that arrives in a crate and stops there is not worth buying. Six things come with every one we sell.

• On-site installation and commissioning by a Semsons technician — including the power and compressed-air check for setting machines, and the radiation safety check for XRF.
• Operator training on site, and we stay until the operator can run the machine alone. A setting machine only reaches its rated speed when the operator knows it, which is a training question rather than a hardware one.
• Genuine spare parts, dispatched the same day on stocked items from Mumbai and Rajkot.
• Service in 16+ Indian cities, through 40+ distributors and 450+ dealers — so a unit that expands beyond its home city keeps the same support.
• A 12-month warranty, extendable, on setting machines. One year on the XRF analyzer. The ST4820 ultrasonic cleaner is replaced within 30 days of delivery if a manufacturing defect is verified.
• CE, ISI and ISO 9001 certified equipment.

Machines are quoted against a booking amount, with the balance due on installation. The full terms are on installation, training, spares and service, and delivery across India and export covers how they reach you.

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Who are Semsons Tech?

A Mumbai family business, founded in 1978 by Babulal Ravchand Mehta and now run by the third generation.

Semsons Tech has won the JMA Award from the Jewellers Manufacturers Association, supplies 34+ export markets, and runs 16+ warehouses across India. The head office is at Semsons Plaza, Gaurav Garden Complex, Bandar Pakhadi Road, Kandivali West, Mumbai 400067. The Rajkot office is on Gulab Wadi Society Street-1, Nana Mava Road, near the Marketing Yard.

The company's own tagline is “Where Quality Speaks For Us.”

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Common questions

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Guides and reference

The detail behind each decision on this page.

• Which tray and nozzle do I need? The full pairing chart, 0.8 mm to 3.0 mm.
• Automatic versus manual setting Speed, accuracy and labour — and how to work out whether a machine pays for itself.
• Single versus double station Pro Mini or X4 Pro Plus, side by side.
• What size ultrasonic cleaner? Tank size by batch, and 40 kHz against 28 kHz.
• Wax setting silicone How to apply it, how often it can be re-used, and when to replace it.
• Glossary Every term used across these pages, defined.
• Installation, training and spares What comes with every machine.
• Delivery and export How machines and consumables reach you.

By city: Mumbai and SEEPZ · Rajkot.

Where the market figures come from

• Gem and Jewellery Export Promotion Council (GJEPC) and Exim Bank, Making Gems and Jewellery Clusters Exportable — the cluster mapping of 17 high-potential districts.
• GJEPC and NCAER, Cluster Mapping of Gem and Jewellery Sector in India.
• World Gold Council, on the structure of India's gold jewellery market.

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