Edgy Shapes

Learned a new shape today...rhombic dodecahedron

"In geometry, the rhombic dodecahedron is a convex polyhedron with 12 congruent rhombic faces. It has 24 edges, and 14 vertices of two types. It is a Catalan solid, and the dual polyhedron of the cuboctahedron."

I found this label on a mineral specimen I was checking out in Manchester museum in the pic below.

I love how a natural shape like this mineral can have such amazing angles. There's a design there that looks like it has been made somehow but at the same time it's not perfect, it is just how it's formed from it's structure and environment.

Quartz crystals have a really interesting shape. Slightly prismatic but with nibbled edges like an early glass artefact which has worn but survived underground. A lovely chunk of quartz makes up this one-off ring available at Craft & Culture. The silver lustre brings out the facets of the sculpted ring and it's polished to a metallic shine.

This piece is available online now at Craft & Culture

Rainbow Rhombus

Is it a ring, or a Viking Compass to locate the Hidden Sun?

Recent bespoke Iceland Spar ring

Iceland Spar is an amazing material, usually found as a rhombohedral crystal and part of the calcite family. Calcite has a unique property of double refraction. This means that when rays of light enter the stone it is split, creating fast and slow beams of light. This causes the effect of anything and everything being viewed through Calcite appearing twice. This unique double refraction can also cause a rainbow effect in examples that have small crystal fractures. 

It is also thought to be what was known from medieval Icelandic texts as "Sunstone", used by the Vikings for navigation its light-polarizing property helping determine the direction of the sun on cloudy days!

Here's a triangular prism refracting light

An Iceland spar Sunstone was recovered from the Elizabethan ship Alderney  that sank in 1592, suggesting it was still used for navigation after the invention of the magnetic compass. Today it is used in the manufacture of Nichol Prisms, an integral part of optical instruments and polarizing microscopes.

In Norse mythology the sun is personified by the goddess Sól or Sunnabrother/companion of the Moon god Máni.

In the poem Völuspá, a dead völva recounts the history of the universe, here it is translated by Benjamin Thorpe:

The sun from the south, the moon's companion,

her right hand cast about the heavenly horses.

The sun knew not where she a dwelling had,

the moon know not what power he possessed,

the stars knew not where they had a station.

The Wolves Pursuing Sol & Mani John Charles Dollman (1851–1934)

Today is the longest day of the year, when the Northern Hemisphere receives the most sunlight. The official start of SUMMER! With this ring you can always find the sun, even when it's hidden. Happy Solstice!