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Durability, not prestige

Every stone on the Mohs scale

Friedrich Mohs arranged ten reference minerals by which could scratch another. The resulting scale runs from talc at 1 to diamond at 10, but its intervals are not equal: the leap from corundum to diamond is far greater than a single step suggests. Select any point to meet the stones that sit there.

1 · Talc10 · Diamond

Hover or focus a stone on the scale above.

The chemistry of colour

Six elements behind many gemstone colours

Quartz, corundum and beryl can all be colourless in pure form. Minute traces of other elements absorb particular wavelengths of light, transforming what the eye sees. The same element can produce entirely different colours inside different mineral structures.

Modern and traditional

What belongs to your month?

The modern Western list was standardised by American jewellers in 1912 and revised over the following century. Select a month to compare its modern stones with older traditional associations.

Birth Month
Provenance With a Plot

Three Stones That Became History

Most gemstones live quiet lives in rings and pendants. A handful ended up in the middle of empires.

Keeping what you have

Care by durability and sensitivity

Hardness measures resistance to scratching, not resistance to every kind of damage. Cleavage, porosity and treatment matter too. The safest routine begins with knowing the stone.

Hard and generally resilient

For untreated diamond, sapphire and ruby, use warm water, a drop of mild soap and a soft brush. A sharp impact can still chip a stone, and filled or fractured material needs gentler care.

Hard, but impact-sensitive

Topaz, tourmaline, aquamarine and zircon resist many scratches but may cleave, abrade or react badly to sudden temperature changes. Clean gently and avoid impacts.

Porous, organic or delicate

Wipe opal, pearl, coral, turquoise, amber and moonstone gently; do not soak them. Keep them away from heat, perfume and household chemicals. Put them on last and take them off first.

Avoid ultrasonic and steam cleaning for emerald, opal, pearl, coral, turquoise and amber. When a treatment is unknown, use a soft damp cloth and seek professional advice before deeper cleaning.
Sources and methodology

What we know—and how we say it

This encyclopedia separates measurable gemmology from market practice, documented history and living tradition. Each deserves its own language and level of certainty.

Gemmology

Mineral family, hardness, formation, optical behaviour and treatments are synthesised from established gemmological and mineralogical references.

Market context

Price bands provide broad Indian retail context, not live quotations. Origin, treatment, certification, size and quality can change value substantially; verify before buying.

Tradition

Navagraha, Navaratna and cultural associations are documented as traditions. They are not presented as scientific evidence or personal prescriptions.

Primary reference families include GIA gem education, museum collection records, standard mineralogical literature and documented Navagraha and Navaratna traditions. Dates are retained when they materially affect a historical or market-sensitive claim.