Materials and Features:

• Premium Sparkle Amber Rhodoid Core: High-grade industrial cellulose acetate (Rhodoid) formulation by G. Convert SA. The optical-grade material features a rich amber body with an internal crystalline structure that catches and refracts light, giving it a subtle under-surface "sparkle" without using cheap, topical glitter flakes.

• Three-Dimensional Dark Brown Swirling: Suspension-blended with dense, dark brown to black internal filaments. Because the pigmented compound was mixed directly into the base before curing, the currents float deep within the dome, creating a clear visual space and layered depth beneath the high-gloss skin.

• Industrial Hemispherical High-Dome Profile: Stamped using a deep, round cylindrical steel die cavity to create a dramatic 10.5mm steep dome geometry. The smooth, seamless 180-degree outer curvature maximizes light capture across the highly polished perimeter.

• Tri-Point Factory Ejector Footprints: The flat interior back-facing wall preserves three distinctly visible, evenly spaced circular shallow crater markings. These diagnostic tooling features are permanent signatures left when mechanical push-rods broke the cooling vacuum to pop the hot polymer button out of the mold.

Type: Continuous hemispherical high-dome button post earrings configured for pierced ears.

Age/Origin: Circa 1950’s / Oyonnax, France (G. Convert SA Industrial Works)

Marks: Unsigned Factory Original (Verified via the featherlight 4.2g combined pair mass, deep 10.5mm dome architecture, and signature tri-point mechanical back-wall ejector markings).

Other: These earrings represent an excellent example of high-volume post-war commercial technical mastery from the historic Oyonnax valley plastics cluster. The unique material formulation produces a distinct, musical marble-clank resonance when handled together. The components have successfully passed comprehensive structural screening, showing a completely negative chemical reaction to Simichrome testing and producing zero phenolic or camphor odors under localized thermal testing, confirming a stable, non-degraded mid-century cellulose acetate matrix.

Measurements:

• Weight: 4.2g (Combined pair mass; exhibits a surprisingly light, comfortable heft relative to its deep volumetric thickness)

• Dimensions: Diameter: 0.75" (18mm) | Overall Thickness: 10.5mm deep dome (including surface-mounted metal plates)

Condition: Excellent vintage condition. The rich sparkle amber base and dark brown swirling filaments remain beautiful, crisp, and entirely free of internal material clouding, environmental degradation, or UV-induced fading. Reflecting their authentic organic casting, one earring naturally features a more dense, visible swirl pattern than its matching counterpart. The high-gloss exterior surface is structurally immaculate, retaining a uniform, mirror-bright buffed sheen across all faces. The uniform silver-tone magnetic plates and post wires sit surface-mounted directly on the flat backing, firmly and securely seated with zero loose alignment or modern structural losses.