Phantom quartz

Phantom quartz is a kind of quartz in which the outline of a smaller crystal of the same shape, the “phantom”, can be seen inside. These inner lines mark the boundary of an earlier growth stage of the crystal. The crystal stops growing for a while, tiny bubbles or specks of another mineral, such as green chlorite, settle on its faces, and when growth resumes this thin layer is left inside. Like all quartz it is silicon dioxide (SiO₂), and phantoms can appear in many varieties of quartz.

Collecting: crystals with phantoms are favourites of mineral collectors and are displayed in museums such as the Oxford University Museum of Natural History and the Bündner Natural History Museum in Switzerland. Science and teaching: because phantoms show the stages a crystal went through as it grew, they are a good example for explaining crystal growth. Decoration: rough crystals, and pieces polished to bring out the phantom, are used as ornaments and pendants.

It has a hardness of 7 on the Mohs scale. It scratches glass and steel; a steel knife cannot scratch it. Its specific gravity is 2.65–2.66 g/cm³.

Its best-known localities: Garland County, Arkansas, USA; Mount Ida, Montgomery County, Arkansas, USA; Gouveia, Minas Gerais, Brazil.

Inside a transparent crystal you see the silhouette of a smaller crystal with the same pointed tip and straight sides, as if there were a crystal within a crystal. The phantom line can be green (chlorite), white (tiny bubbles), grey or black (fine rock particles). Some crystals hold several nested phantoms, each marking a separate pause in growth.

On the “street to diamond” value ladder it sits on step 5 of nine: Ornamental stone. The value of phantom quartz depends mostly on the clarity of the host crystal and on how sharp and contrasting the phantom is: crisp, vivid green or white phantoms inside a water-clear crystal are the most sought after. Several nested phantoms, undamaged points and the size of the crystal also add value. Because quartz is a common mineral, phantom quartz is not an expensive stone; its value comes mostly from its beauty as a collector's specimen.

Today crystal-therapy websites and stone sellers present phantom quartz as a symbol of transformation and “rebirth”, and claim that it helps personal and spiritual growth. The same sources claim that meditating with phantom quartz helps people let go of past pain and grief. There is no scientific evidence that phantom quartz helps spiritual growth or coping with grief; the phantom inside is a physical trace left by a pause in crystal growth. Lasting grief and emotional distress call for a professional. This section reports beliefs; it is not health information. There is no scientific evidence for these claims and no stone replaces medical treatment.