Golden Spiral Pendant - Math Jewelry
- Free worldwide shipping to most countries
This necklace is inspired by the golden spiral. The golden spiral is a logarithmic spiral whose growth factor is the golden ratio, a mathematical constant. The golden ratio, designated by the Greek letter "phi," equals 1.618 and represents the ratio of a line cut into two segments of different lengths such that the ratio of the whole segment to that of the longer segment is equal to the ratio of the longer segment to the shorter segment. The golden spiral approximates a fibonacci spiral, but only at later turns.
There are many examples in nature of organisms that display the golden spiral in their design, for example, spiraled seashells and snail shells, galaxies, hurricanes, pine cones, sunflower seed heads, and petal placement in many flowers. To honor its importance in nature, the Ontogenie golden spiral pendant is adorned with arches that represent the inner walls of a seashell.
The Golden Spiral pendant is 2 cm (0.8 in) wide and 3 cm (1.2 in) long below the loop.
The pendant is 3D printed in solid sterling silver or 14K gold plated brass, finished with a 45 cm/18 inch long sterling silver or gold plated silver chain*, and is ready for gift giving with a gift box, polishing cloth, and care instructions.
*While a 45 cm/18 inch fits most, other chain lengths are available. At checkout, write a note indicating your preference.
Jewelry Shipping
(please scroll down for T-shirt shipping information)
Jewelry in stock at Ontogenie will be shipped within 1-2 days.
Delays may occur due to coronavirus-based shipping disruption.
| Australia | UPS 6-8 days | free |
| Canada | UPS 3-5 days | free |
| European Union | UPS 2-9 days | free |
| Germany | DHL 1-2 days | free |
| Hong Kong | DHL 3-5 days | free |
| Iceland | UPS 3-5 days | free |
| Japan | UPS 3-5 days | free |
| Norway | DHL 2-4 days | free |
| Singapore | UPS 3-5 days | free |
| South Africa | UPS 4-6 days | free |
| Switzerland | DHL 2-4 days | free |
| Taiwan | UPS 3-5 days | free |
| United Kingdom | UPS 3-5 days |
free |
| United States | UPS 3-5 days | free |
| Rest of World | please contact ontogenie3d@gmail.com |
You will be notified by mail when your order ships and given a tracking number so that you can follow your shipment. Ontogenie jewelry is shipped internationally from Germany via UPS and DHL. Your jewelry will be gift-wrapped in original Ontogenie packaging.
Please note that shipments may be delayed for reasons beyond my control. In the unlikely event that your jewelry shipment is held by your local customs office, you are responsible for paying any fees incurred.
T-Shirt Shipping
T-shirt shipping is free.
T-shirt printing requires 2-7 days fulfilment time. After fulfilment, your shipment should arrive in 3-10 business days.
In the unlikely event that your T-shirt shipment is delayed by your local customs office, Ontogenie is not liable for any fees incurred.
Ontogenie jewelry is 3D printed in wax and then cast in solid sterling silver, solid bronze, or solid brass plated with 14K gold. The sterling silver and bronze pieces will tarnish and discolor slightly over time. This is completely normal for these materials. Moisture, chlorine, sulfur (i.e. onions, garlic), hand sanitizers, and the oils in your skin may accelerate the tarnishing process. I recommend that you don't wear the jewelry in water, e.g., while bathing, showering or swimming. After wear, it's a good idea to polish the jewelry with a soft cloth and store it in a dark, dry place to slow the oxidation which causes tarnish.
If the jewelry should tarnish, it can be returned to its original brilliance and color by using a gentle, non-abrasive cream silver polish. I do not recommend silver wipes, baking soda or toothpaste as these can scratch the surface of mirror polished jewelry.
Highly detailed and textured pieces will be more difficult to polish because of surface variations. To polish these, I recommend using a very soft toothbrush with the cream silver polish to allow cleaning of small crevices. After polishing, you can remove excess polish by rinsing the jewelry in water and then washing the piece with a gentle detergent followed by a final water rinse.
The gold-plated materials, however, should not be vigorously polished as the plating is likely to wear off over time. The gold-plated materials are much less susceptible to tarnishing and will probably never need to be polished except with a soft cloth to remove fingerprints.
All of the jewelry should be protected from impact against hard surfaces as this can cause scratching.
3D printing offers a diverse array of materials for jewelry design.
Cast metals
The cast metals are first 3D printed in wax with a high resolution printer using my design file. A plaster mold is then poured around the wax and the plaster is allowed to set. The wax is melted away, the plaster form is filled with molten metal and the metal is allowed to harden (lost wax casting). After being released from the mold, the metal piece can be polished to a shiny gloss or left unpolished.
The photo on the left shows the Mitochondrion pendant design printed in polished sterling silver, polished bronze and 14K gold plated brass.
Both silver and bronze will tarnish slightly over time. Bronze tarnishes to a warm brown and silver to a darker gray. This is completely normal for these materials. They can both be brightened with a gentle silver polish and soft cloth. The 14K gold plated brass material is a brass with a thin coating of 14K gold. Care should be taken that the plated jewelry is not exposed to friction as this could result in small areas of the plating rubbing off.
If you would prefer that your jewelry be printed in solid platinum, 14K gold, 14K rose gold, 14K white gold or 18K gold, please contact me for a nonbinding quote on the price.
Steel
In contrast to the cast metals, steel is created by 3D printing a liquid binder onto a bed of steel powder. The resulting print is infused with bronze and baked in an oven to harden.
Steel can also be plated with various metals after printing.
For more information on the chemical composition of each material, please consult the following:
Sterling Silver: 93% Silver, 4% Copper, 3% Zinc
Brass: 80% Copper, 15% Zinc, 5% Tin
Bronze: 90% Copper,10% Tin Alloy
Gold plated brass (14K electroplated gold on brass)
Steel: 60% Steel, 40% Bronze matrix material