The Complete Ruby Guide

Table of Contents

  1. Ruby Consumer Information
  2. Ruby References in Antique Gemological Books

Ruby Consumer Information

As provided and validated by various gemmological organizations, laboratories and the "World Jewelry Confederation CIBJO"


Rubies are extremely durable due to their hardness and toughness – second after diamond on the Mohs Hardness Scale. Ruby jewellery may be cleaned in an ultrasonic cleaner, or it may be steamed. But this should follow close inspection to determine if there are any surface reaching fissures that could expand, or if oils or dyes are present. As with most gemstones, a soft moistened cloth, or a soft bristle toothbrush may be used to clean the gem


Transparency: heating dissolves or partially dissolves fine rutile needles thereby increasing the clarity and transparency of the gem.
Transparency: High lead content glass is sometimes used to fill surface reaching fissures, pits or cracks in certain rubies/ corundum increasing transparency
Color: heating helps remove purplish or brownish colour components in some gemstones, resulting in stronger red colours
Color strengthening: diffusion of colour causing elements through intense heating


Color and transparency: heat treatment (partially) dissolves fine rutile needles thereby increasing the clarity, transparency and remove brownish components
Color strengtening: diffusion of colour causing elements through intense heating
Color: surface reaching fissures may be treated with oil or dyes, resulting in stronger colours. Treatment not durable and requiring special care
Improving transparency: lead glass filling in cavities and fissures


“Silk,” networks of fine, included rutile needles, intersecting at 60 degree angles, are commonly seen in natural ruby
Included crystals of zircon, and related stress fractures (or halos) are sometimes seen. Liquid-filled “fingerprint” inclusions are also common
Note some of these identifying characteristics may disappear, change or be diminished as a result of treatments
The presence of silk or other inclusions is often valued since it not only points to a gem’s natural origin but it also suggests the gem has not been treated


In the market, rubies are found in a variety of shapes and cutting styles
Ovals are cushions are the most common, but rounds are also seen, as are other shapes, such as the heart or emerald cut
Slight premiums are paid for round stones, while slight discounts apply for pears and marquises
Stones that are overly deep or shallow should generally be avoided

Ruby References in Antique Gemological Books

Famous Ruby Mines | Mining Areas

Famous Victorian Jeweler Edwin Streeter led a consortium against Baron Rothschild to obtain the Burma Ruby Mining rights.
Edwin Streeter on Ruby Mines
Streeter’s connection with Burma Mines
Tavernier was one of the leading gem dealers of the 17th century who brought back the diamond that later became the “Hope Diamond”.
Tavernier on Ruby Mines in Burma
Badakshan Ruby | mines in Badakhshan
Burma, Ceylon, Australia and “Lord of the Rubies
List of Ruby mine locations around the world, and more recent status of those mines

Famous Rubies | Ruby Stories

Famous Rubies: Orpen on the Black Prince’s Ruby | Tavernier on famous Rubies from the Orient | Exceptional European Rubies
Shakespeare‘s use of Rubies and Ruby lore and superstitions
The Case of the Nun’s Ruby (Kornitzer)
Some Gemstone Classics
An amazing standard work of George Kunz: Gems of North America: Rubies
Edwin Streeter on Rubies
Rev. King on Ruby or Carbuncle

Chemical | Physical Properties

Chemical analysis of Ruby
More Chemical and Physical Properties

Some more Ruby sources

Catelle on Ruby and Sapphire
The curator of Chicago’s Field Museum of Natural History between 1894-1904. Oliver Farrington on Rubies, Sapphire and other Corundum

Ruby References before 1700

10th Century Islamic scientist Al-Biruni with 45 page overview of use of Rubies, famous Rubies etc in the East.
Theophrastus use of Anthrax, Ruby and most likely Red Garnet
Chapuzeau (1652) about Rubies from the Orient and Nicols (1652) Carbuncle or Ruby
Agricola on Carbuncle and Ruby
Check Albertus Magnus on Rubies

Balas Rubies from Badakshan (Badakschan)

Medical properties by 9th century scientist Al Biruni
Spinel (Balas Ruby) as discussed by Streeter