The Edwardians loved novelty jewels and, to judge by the numbers of phenomenal gems that appear in men's stickpins and in the novelty brooches that women wore, were fascinated by unusual stones. Australian opals with their play of colour, cat's-eye chrysoberyls with their mysterious chatoyancy, and star sapphires displaying perfect asterism captured the Edwardian imagination, offering optical effects that seemed almost magical in gaslight and early electric illumination.
These phenomenal gems—stones displaying special optical effects—provided jewellers with natural wonders that required no enhancement beyond careful cutting and setting. Each stone was unique, its optical phenomena making it instantly recognisable and impossible to replicate. For Edwardian society, these gems represented nature's artistry at its most mysterious and compelling.
Understanding Phenomenal Gems
Phenomenal gems display optical effects caused by their internal structure, inclusions, or composition. These effects only appear under specific conditions of lighting and viewing angle, making the stones seem alive with movement and change. The Edwardian period coincided with scientific understanding of these phenomena, adding intellectual interest to aesthetic appeal.
Types of Optical Phenomena
The major optical phenomena prized by Edwardians included chatoyancy (cat's-eye effect), a sharp band of light across a cabochon-cut stone; asterism (star effect), showing four, six, or twelve-rayed stars; adularescence, the ethereal blue sheen of moonstone; play of colour, the spectral display in precious opal; colour change, dramatic shifts between different light sources; and aventurescence, sparkling metallic reflections within the stone.
Each phenomenon resulted from specific internal structures: parallel fibres or channels creating cat's-eyes, intersecting needle-like inclusions forming stars, layered structures producing adularescence, and ordered spheres of silica creating opal's play of colour.
The Appeal of the Unusual
Edwardian society's fascination with phenomenal gems reflected broader cultural interests in science, mystery, and the exotic. These stones offered conversation pieces that demonstrated both wealth and sophisticated taste. Their rarity and the impossibility of creating synthetic versions made them particularly desirable for those seeking unique jewellery.
Cat's-Eye Chrysoberyl: The Finest Phenomenon
Stickpins proved the perfect vehicle for displaying special gemstones such as spectacular pearls or cat's-eye chrysoberyls. The chatoyancy of cat's-eye stones—that distinctive band of light that moves across the surface—fascinated Edwardians with its suggestion of a living eye watching the observer.
Quality Factors
The finest cat's-eye chrysoberyls displayed specific characteristics that Edwardian connoisseurs understood and valued. The eye should be sharp and well-defined, not fuzzy or broken. Under single light source, the stone should show clear "milk and honey" effect with one side light, one dark. The eye should remain visible under various lighting conditions and perfectly centred when the stone is properly cut. The body colour ranged from honey-yellow through greenish-brown to emerald green, with golden colours most prized.
Setting and Display
Cat's-eyes were typically set simply to showcase their phenomenon. High bezels protected the cabochon whilst allowing light from all angles. Yellow gold complemented honey-coloured stones, while white metals enhanced greenish examples. Stickpins allowed the stones to move with the wearer, making the eye appear to follow observers—an effect that delighted Edwardian society.
Beliefs and Superstitions
Cat's-eyes carried powerful protective symbolism. They were believed to guard against the evil eye, preserve wealth and prevent financial loss, protect travellers from danger, and cure or prevent eye diseases. Military officers particularly favoured cat's-eye stickpins, believing they provided protection in battle.
Australian Opal: Fire from Down Under
Australian opal discoveries in the late Victorian period revolutionised the opal market, providing material of unprecedented quality just as Edwardian jewellery reached its creative peak. These opals displayed play of colour far exceeding anything previously known, with entire spectrums dancing across their surfaces.
Types and Qualities
Australian opals appeared in several varieties, each with distinct characteristics. White opal from Coober Pedy showed delicate play of colour against milky backgrounds. Black opal from Lightning Ridge displayed brilliant fire against dark body colour, the most valuable variety. Boulder opal retained ironstone matrix, creating natural pictures. Crystal opal was transparent to translucent with internal fire. Each type required different approaches to cutting and setting.
Colour Patterns
Edwardian jewellers recognised and valued specific colour patterns. Harlequin showed distinct rectangular patches of colour, the most prized pattern. Pinfire displayed tiny points of colour across the surface. Broad flash exhibited large areas of single colours. Rolling flash changed colour as the stone moved. Straw pattern showed thin parallel lines of colour. The most valuable stones combined multiple patterns with full spectrum colours.
Design Applications
Opals appeared throughout Edwardian jewellery, their versatility suiting various design approaches. Large stones became centrepieces for brooches and pendants. Smaller opals created colour accents in complex designs. Opal matrix provided backgrounds suggesting landscapes or seascapes. Doublets and triplets made precious opal accessible to middle-class buyers.
Overcoming Superstition
Despite Victorian associations with bad luck, opals returned to favour during the Edwardian period. This rehabilitation resulted from Queen Alexandra's public wearing of opals, Australian marketing emphasising the stones' British Empire origins, scientific explanation dispelling supernatural fears, and the stones' undeniable beauty overcoming superstition.
Star Stones: Asterism in Sapphires and Rubies
Star sapphires and rubies displaying perfect six-rayed stars ranked among the most prized phenomenal gems. The star effect, caused by oriented needle-like inclusions of rutile, created the illusion of light trapped within the stone.
Quality Assessment
Edwardian jewellers evaluated star stones by specific criteria. Stars should be sharp and complete with all rays visible, centred on the dome of the cabochon, visible in normal lighting without direct illumination, and mobile, appearing to glide across the surface as the stone moves. Body colour affected value, with cornflower blue sapphires and pigeon blood rubies most desired.
Famous Star Stones
Several celebrated star stones appeared in Edwardian jewellery. The Star of India, discovered in Ceylon, became centerpiece of notable collections. Royal collections included exceptional examples from Burma and Ceylon. Society ladies competed to own the finest specimens. These stones often carried names and documented histories, adding to their allure.
Setting Techniques
Star stones required careful setting to display their phenomena. High cabochons needed secure mounting whilst remaining visible from all angles. Open-backed settings allowed light through the stone. Prong settings minimised metal contact. Some pieces featured rotating mechanisms allowing the wearer to adjust the star's position.
Alexandrite: The Changeling Gem
Alexandrite's dramatic colour change from green in daylight to red in incandescent light perfectly suited Edwardian society's movement between daytime and evening activities. This rare chrysoberyl variety, discovered in Russia's Ural Mountains, remained the ultimate prestige gem.
The Colour Change Phenomenon
Fine alexandrite showed complete transformation between light sources. In daylight: emerald green to bluish-green. In candlelight or gaslight: raspberry red to purplish-red. The transition should be dramatic and complete, not muddy or brown. The finest stones showed additional pleochroism, displaying different colours from different angles.
Rarity and Sources
Original Russian alexandrites were nearly exhausted by the Edwardian period, making them extraordinarily valuable. Ceylon (Sri Lanka) provided smaller stones with less dramatic colour change. Brazilian discoveries late in the period offered new material. Each source produced distinctive characteristics collectors learned to recognise.
Design Significance
Alexandrite's rarity meant it appeared primarily in important jewels. Stickpins showcased single exceptional stones. Rings featured alexandrites surrounded by diamonds. Royal and noble collections included alexandrite parures. The stones' colour change made them particularly suitable for jewels worn from day into evening.
Moonstone: Ethereal Beauty
Moonstone's ethereal adularescence—a blue sheen floating just below the surface—appealed to Edwardian romantic sensibilities. This feldspar's mysterious glow suggested moonlight on water, earning its evocative name.
Quality and Origin
The finest moonstones came from Ceylon (Sri Lanka) and Burma (Myanmar), displaying strong blue adularescence against colourless bodies, smooth, unblemished surfaces, and good transparency allowing the effect to show clearly. The optical effect resulted from alternating layers of different feldspars, creating light interference.
Design Applications
Moonstone's softness required protective settings, influencing design choices. Carved moonstones became fashionable, particularly faces suggesting the "man in the moon." Cabochons were bezel-set for protection. Multiple moonstones created ethereal effects in tiaras and necklaces. The stones often accompanied star motifs, reinforcing celestial themes.
Symbolic Associations
Moonstones carried romantic and mystical associations including love and reconciliation, intuition and psychic abilities, protection during travel, especially over water, and feminine power and goddess connections. These associations made moonstone jewellery popular for wedding gifts and lovers' tokens.
Other Phenomenal Gems
Beyond the major phenomenal gems, Edwardians collected various stones displaying optical effects, each offering unique appeal.
Sunstone
Sunstone's aventurescence—sparkling metallic reflections—created sunny effects perfect for daytime jewellery. Oregon sunstones with copper inclusions showed particular brilliance. These stones appeared in sporting jewellery and summer pieces, their warm sparkle suggesting sunshine and vitality.
Labradorite
Labradorite's iridescent play of colours—labradorescence—fascinated Edwardian jewellers. The effect showed blues, greens, golds, and sometimes reds flashing across grey backgrounds. Finnish spectrolite showed the full spectrum. These stones suited Art Nouveau-influenced designs with their organic, mysterious appearance.
Tiger's-Eye and Hawk's-Eye
These quartz varieties showed chatoyancy in golden-brown (tiger) or blue-grey (hawk) colours. More affordable than chrysoberyl cat's-eye, they appeared in gentlemen's jewellery and sporting pieces. The stones' fibrous structure created silky lustre beyond the cat's-eye effect.
Curiosities and Unusual Stones
Edwardian jewellers incorporated numerous unusual stones selected for unique properties rather than traditional beauty.
Phenomenal Diamonds
Rare diamonds showing phenomena commanded extraordinary prices. Chameleon diamonds changed colour with heating or dark storage. Phosphorescent diamonds glowed after exposure to ultraviolet light. These scientific curiosities appealed to educated collectors.
Included Quartzes
Quartz crystals containing interesting inclusions became collectible. Rutilated quartz with golden needle inclusions suggested captured sunshine. Tourmalinated quartz with black tourmaline crystals created dramatic patterns. Phantom quartzes showed ghost crystals within, fascinating geological records.
Petrified Materials
Fossilised materials appealed to Edwardian interest in natural history. Petrified wood showed wood grain in stone. Fossilised coral displayed organic patterns in mineral form. Ammolite from fossilised ammonites showed iridescent colours. These materials bridged jewellery and scientific specimen.
Setting and Displaying Phenomenal Gems
Phenomenal gems required specific approaches to cutting and setting that maximised their optical effects.
Cutting Considerations
Most phenomenal gems were cut as cabochons to display their effects. The dome height affected phenomenon visibility. Orientation during cutting was crucial for proper effect display. Some phenomena required specific crystallographic orientation. Skilled cutters could make or destroy a stone's potential.
Mounting Techniques
Settings balanced security with visibility. Minimal metal contact preserved optical effects. Open backs allowed light transmission. Heights were calculated to optimise viewing angles. Some pieces featured adjustable or rotating mounts. The metal choice complemented without competing with the phenomenon.
Lighting and Display
Edwardian jewellers understood lighting's importance for phenomenal gems. Different effects required different illumination: single light source for cat's-eyes and stars, mixed lighting for colour-change stones, and diffused light for adularescence and iridescence. Evening events' varied lighting made phenomenal gems particularly effective.
Identification and Authentication
Identifying genuine phenomenal gems requires understanding both the phenomena and period manufacturing techniques.
Natural versus Synthetic
While synthetic phenomenal gems existed by the Edwardian period, most were easily distinguished. Natural phenomena showed irregularities and variations. Synthetic stars were often too perfect. Natural inclusions differed from synthetic characteristics. Period documentation helps establish authenticity.
Treatments and Enhancements
Some Edwardian-era treatments affected phenomenal gems. Surface diffusion could induce asterism in sapphires. Backing materials enhanced or created effects. Doublets and triplets simulated solid stones. Understanding period practices helps identify original condition.
Condition Issues
Phenomenal gems present specific condition challenges. Surface wear can diminish optical effects. Fractures interrupt phenomena display. Some stones are inherently fragile (opal, moonstone). Restoration options are limited without damaging effects. Condition significantly impacts value.
Edwardian phenomenal gems captured nature's most mysterious optical effects in wearable form, satisfying the era's desire for novelty, science, and beauty combined. From the watchful eye of chrysoberyl cat's-eye to the celestial fire of Australian opal, these stones offered Edwardian society conversation pieces that were simultaneously natural wonders and artistic achievements. For modern collectors, phenomenal gems from this period represent exceptional opportunities to own unique pieces that cannot be replicated, each stone a natural artwork enhanced by Edwardian craftsmanship. Understanding these gems' special properties, period preferences, and proper display enhances appreciation of their enduring appeal and remarkable beauty.