Styled shot of glass accent tables styled with colourful crystal vases and candle holders

Material In Focus: Cracking the Code on Crystal vs Glass

Need some clarity on Crystal versus Glass? We’re getting technical with the basics of crystal classification to clarify any confusion.

Riddle me this, if all crystal is glass, but not all glass is crystal, then what is crystal?

Lead glass, commonly referred to as Crystal, is a type of glass which is widely used in the manufacture of drinkware, glassware and decorative objects due to its clarity, brilliance and durability. Now before you start to worry about the inclusion of lead in your crystalware, rest easy, because the moniker while still in use is often replaced with the more suitable term Crystal. Modern manufacture of Crystal Glass has seen lead replaced with other substances such as zinc oxide or potassium oxide which do not pose a risk to health in the way lead can in drinkware.

The Hard and Soft of It:
You may be thinking how can crystal be soft? Well, these two terms also relate to whether the crystal in question contains lead or is lead-free. Lead crystal aka soft crystal gained the moniker due to the fact its composition is softer than lead-free crystal and can be moulded. This type of crystal is often used to create bowls and vases and other objects that require manipulation but are not used for drinking.

Lead-free crystal aka hard crystal is unable to be moulded or manipulated in the way soft crystal can, but can undergo transformation through cutting, grinding and polishing for an intensely shiny surface.

Starting to see the light on Crystal? Let’s continue onto one of the main qualifiers of quality, clarity and brilliance of Crystal. Introducing, the Refractive Index.

What Is the Refractive Index and What Does It Mean?

Without getting overly technical, the refractive index is a unit of measure which indicates the measure of light bending of an object. This unit of measure refers to how much light is “refracted” aka bent and reflected as it enters an object as well as it’s ability to reflect and transmit light passing through it.

The higher the Refractive Index number is = the greater clarity and refraction of the material.

It is generally considered that a material with a refractive index of >1.5 is considered crystal whereas <1.5 would be classified as glass.
As a reference point, some commonly known materials and their refractive indexes are:

Acrylic / Lucite / Perspex ~ 1.49
K9 Crystal ~ between 1.51-1.52
Diamonds ~ 2.41

As you may deduce from the materials mentioned above, the greater the refractive index, the greater the purity, clarity and quality of a material. So if you want your homewares to sparkle as brightly as your diamond rings, we suggest opting for scintillating crystal pieces of 1.5 and above.

The 411 on K9 Crystal:
K9 Crystal is a term worth familiarising yourself with. It is a lead-free form of high-quality borosilicate (a type of glass that is more resistant to temperature fluctuations and thermal shock than regular glass, therefore less likely to fracture or shatter) crystal glassware which is light, can be polished, and has a high refractive index indicating it’s impressive light reflective properties. This winning combination of durability and refraction has seen a rise in popularity of this crystal in decorative objects.

Ready to reflect (pun intended) your impeccable style in your home? Shop our Crystal Coded collection and welcome the sparkling reflective light throughout your home, morning to night!

Happy Styling x GIGI&TOM

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