Gemstone Buying Guide
Ruby | Emerald | Pearl | Coral
A Simple Guide to Buying Gemstone Jewellery
Gemstones are one of the oldest forms of adornment known to humankind. Long before they found their way into rings and necklaces, they were carried as talismans, offered to deities, and traded across continents. When you wear a gemstone, you are wearing something with a story that stretches back thousands of years.
This guide is for you, whether you are buying your first gemstone jewellery or adding to a collection. We have put together everything you need to know about the four gemstones at the heart of Khazana Jewellery: Ruby, Emerald, Pearl, and Coral.
Gemstones and South India: A Deep History
South India has one of the richest relationships with gemstones in the world. The region was a major hub of the ancient gem trade, and gemstones were woven into every aspect of life.
Temples and Ritual
Before gemstones became jewellery, they adorned temple idols. Rubies, emeralds, and pearls were set into the crowns, necklaces, and garments of deities. Gemstones were believed to carry divine energy, and offering them to a god was considered one of the highest acts of worship. Many of the most famous temple treasures in India still contain gemstones that have never been set into personal jewellery.
Navaratna: The Nine Gem System
One of South India's most enduring contributions to gem culture is the Navaratna, a setting of nine specific gemstones representing the nine celestial bodies in Vedic astrology. Ruby for the Sun, Pearl for the Moon, Coral for Mars, Emerald for Mercury, and so on. This tradition shaped how South Indians thought about gemstones: not just as beautiful objects, but as carriers of cosmic influence. You will still find Navaratna jewellery in every major jewellery store in South India today.
Trade Routes
South India sat at the intersection of major ancient trade routes. Pearls came from the Gulf of Mannar (between Tamil Nadu and Sri Lanka), which was one of the world's most prolific pearl fisheries for over 2,000 years. Rubies and sapphires came from Burma and Ceylon. Emeralds arrived via Arab traders. This access to a wide variety of gemstones meant South Indian craftsmen developed extraordinary skill in working with many different stones — a tradition that continues in the workshops of Chennai, Coimbatore, and Hyderabad today.
From Ritual to Ring: How Gemstones Entered Jewellery
First: Sacred Objects
The earliest use of gemstones was religious and protective. In ancient India, Egypt, and Mesopotamia, gemstones were placed in tombs, embedded in idols, and worn as amulets. Their colour was often what gave them meaning: red stones like rubies and coral were associated with blood, vitality, and fire. Green stones like emeralds were linked to fertility and nature. Lustrous white pearls were connected to the moon and purity.
Then: Medicine
For centuries, gemstones were used in Ayurvedic medicine. Ground pearl powder was prescribed for digestive ailments. Coral was used to treat blood disorders. Rubies and emeralds were set in medicinal preparations called bhasmas. The Charaka Samhita and Sushruta Samhita, two foundational Ayurvedic texts, both discuss the medicinal use of gems extensively. In some parts of India, this practice continues today.
Finally: Jewellery
As trade expanded and craftsmanship developed, gemstones moved from sacred objects and medicine into personal adornment. Royalty wore them first, as symbols of power, wealth, and divine favour. Over time, the tradition moved down through the social hierarchy. By the medieval period, gemstone jewellery was part of important life events: births, weddings, and religious ceremonies. That connection between gemstones and milestone moments is the one most alive today.
The Four Gemstones of Khazana
Ruby
"Ratnaraj" — The King of Gemstones
Ruby is a red variety of the mineral corundum (aluminium oxide). Its colour comes from chromium, and the intensity of that colour determines its value. The finest rubies have a rich, vivid red, sometimes described as "pigeon's blood," with a slight bluish hue.
Where It Comes From
The most prized rubies historically came from Burma (Myanmar), particularly the Mogok Valley. Sri Lankan rubies are lighter, often closer to pink. Thai rubies tend to be darker with a brownish tint. Today, rubies are also mined in Mozambique and Madagascar.
What to Look For
- Colour is the most important factor — look for a vivid, even red without too much brown or pink
- Clarity matters, but most natural rubies have some inclusions. A completely flawless ruby is very rare
- Cut affects how light reflects through the stone; a well-cut ruby should appear bright, not dull
- Treatments are common: heat treatment is widely accepted in the industry and improves colour and clarity
- Unheated rubies with a certification are rarer and more valuable
Emerald
"Panna" — The Stone of Mercury and Growth
Emerald is a green variety of the mineral beryl, coloured by chromium and vanadium. It is one of the four classical precious gemstones alongside ruby, sapphire, and diamond. Emeralds are softer than rubies and sapphires, which makes them more prone to chipping.
Where It Comes From
Colombia produces the most prized emeralds in the world — deep green, with a warm, slightly yellow or blue undertone. Zambian emeralds are darker and slightly more blue-green. Brazilian emeralds tend to be lighter. Indian emeralds, historically mined in Rajasthan, were important in Mughal jewellery.
What to Look For
- Colour should be a rich, deep green; the most valuable emeralds have no yellow or blue tint
- Inclusions are expected and accepted in emeralds. A clean emerald is often a sign of a synthetic stone
- Most emeralds are oiled (filled with resin or oil to improve clarity). This is standard industry practice
- Avoid emeralds with deep fractures on the surface, as these affect durability
- Handle emerald jewellery with care — avoid hard impacts and keep away from harsh chemicals
Pearl
"Moti" — The Gem Born of Water
Pearl is unique among the gemstones in this guide because it is organic — it is produced by a living creature. A pearl forms when an irritant enters an oyster or mussel, and the creature coats it with layers of nacre (a crystalline substance) over time. This process gives pearls their characteristic lustre.
Types of Pearls
Natural pearls, formed entirely without human intervention, are exceptionally rare and expensive. The vast majority of pearls in the market today are cultured pearls, where a nucleus is intentionally inserted into the oyster to initiate the process. Cultured pearls are real pearls; the only difference is that the process was started by humans.
The four main types of cultured pearls are:
- Akoya Pearls (Japan, China) — white to cream, very round, classic lustre
- Freshwater Pearls (China) — a wide variety of shapes and colours, more affordable
- Tahitian Pearls (French Polynesia) — naturally dark, grey to black, with overtones
- South Sea Pearls (Australia, Philippines, Indonesia) — the largest cultured pearls, white to golden
In South Indian Culture
Pearls, known as Moti or Muthu, have the deepest roots in South India. The Gulf of Mannar pearl fishery, which operated off the coast of Tamil Nadu and Sri Lanka, was one of the most famous in the ancient world. Pearls were worn by South Indian royalty and are still a staple of bridal jewellery, particularly in long pearl necklaces (known as Muthu mala), and in classic Hyderabadi multi-strand chokers. Pearl represents the Moon in the Navratna system and is associated with calm, purity, and emotional clarity.
What to Look For
- Lustre is the most important quality; a good pearl should appear to glow from within, not just reflect light off its surface
- Surface quality should be clean, with minimal pitting, spots, or wrinkles
- Shape: perfectly round pearls are the rarest and most valued, but baroque (irregular) pearls have their own appeal
- Nacre thickness matters for durability; thin nacre can chip or peel over time
- Matching matters in strands — look for even colour and size throughout the necklace
Coral
"Moonga" — The Gem of the Sea
Coral is an organic gemstone formed from the skeletal remains of marine polyps. The type used in jewellery is precious coral (Corallium rubrum and related species), found in the Mediterranean Sea and the waters around Japan and Taiwan. Its colours range from pale pink (known as Angel Skin) to deep ox-blood red.
Where It Comes From
Mediterranean coral, sourced from Italy, Spain, and North Africa, is the most historically prized, especially from Torre del Greco, Italy. Japanese and Taiwanese coral is also used widely in jewellery. Due to overharvesting and environmental pressures, genuine precious coral is becoming scarcer and more expensive.
What to Look For
- Colour should be even and consistent — deep red (ox-blood) is most valued, followed by salmon and pink
- Surface should be smooth and free of pits or cracks
- Dyed coral is common — test by rubbing with a damp cloth; genuine coral should not transfer colour
- Imitation coral made from plastic, glass, or resin is widespread; look for a natural, slightly waxy surface texture
Tips for First-Time Buyers
Know What You Are Buying
There is a difference between natural, synthetic, and imitation gemstones. Natural gemstones are formed in the earth (or sea, in the case of pearls and coral). Synthetic gemstones have the same chemical composition but are made in a laboratory. Imitation stones look like the real thing but are made of glass, plastic, or a different mineral entirely. All three can appear in the market. When in doubt, ask your jeweller directly.
Understand the Setting
The metal setting affects how a gemstone looks and how it holds up over time. Gold is the traditional choice for South Indian gemstone jewellery for good reason: it does not tarnish, holds stones securely, and complements warm-toned gems like ruby and coral particularly well. The purity of gold (22KT for traditional South Indian jewellery) affects both the colour and the durability of the piece.
Ask About Maintenance
Different gemstones require different care. Pearls and coral are soft and organic; they react to perfume, sweat, and acids. Emeralds need to be kept away from ultrasonic cleaners. Rubies are harder and more durable, but should still be protected from sharp impacts. Ask your jeweller how to clean and store your piece before you buy.
Frequently Asked Questions
Q: How do I know if a gemstone is real?
Visually, genuine gemstones tend to have natural inclusions and slight imperfections; a stone that looks absolutely perfect may be synthetic. Your jeweller should be able to answer questions about origin and treatment directly.
Q: What is the difference between a natural and a cultured pearl?
A natural pearl forms entirely on its own, with no human involvement. A cultured pearl is grown with the help of a human-inserted nucleus. Both produce real pearls with real nacre. Natural pearls are extremely rare and far more expensive. Most pearls in the market today are cultured pearls.
Q: Can I wear gemstone jewellery every day?
It depends on the gemstone. Rubies are hard and suitable for daily wear. Pearls and coral are softer and more vulnerable, better reserved for special occasions or worn with care, avoiding contact with perfume, water, and acids. Emeralds are beautiful but not ideal for rings or pieces that take regular impact.
Q: Does the colour of a coral affect its price?
Yes. Deep ox-blood red coral is the most prized and expensive. Lighter shades like salmon and pale pink (Angel Skin) are also valuable but less so. Consistent, even colour throughout the piece adds to value. Dyed coral, which is common in the market, should be priced lower than naturally coloured coral.
