Independent guide

The quiet science of natural stone

Onyxium is a reader's guide to natural stone — onyx, marble, travertine and the rest — covering how each one forms, where it belongs and how to keep it looking right for decades.

Stones

Onyx, marble, quartzite — what each is and where it comes from.

Care

Sealing, cleaning and the mistakes that etch a surface.

Design

Using stone so it reads as calm, not busy.

Sourcing

Reading a slab before it becomes a countertop.

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