All of our estimates suggest the crystallization of quartz on time scales of. The formation of quartz requires a gradual and slow cooling of the magma or a gradual precipitation of the hydrothermal solution. Quartz crystals take thousands of years to form. Rapid processes produce massive microcrystalline or semitransparent quartz without the correct crystal shape.
The main problem with either technique is that silicic acid tends to convert to silica gel. However, it is possible to synthesize quartz crystals with a pressure cooker. In 1845, the German geologist Karl Emil von Schafhäutl succeeded in making quartz the first crystal cultivated by hydrothermal synthesis. Modern techniques can be used to grow large single crystals, but you shouldn't expect fabulous gems from a homemade canning system.
Quartz crystals often do not grow continuously, but in short phases. This pulsatile growth is sometimes explained by tectonic activity, which causes a sudden rise of the host rock and a relatively rapid drop in pressure. It's not a crystal that most people want to grow at home, since perfect crystals require specialized equipment. Molecules tend to withdraw from the edges of crystals, and the relationship between the number of edges and the total volume of the crystal does not favor small crystals.
These ghostly layers form over hundreds of years inside a crystal due to the rest of the hot water solutions trapped inside the cavities of the preformed glass. If you're looking for the shape of quartz crystals with golden-yellow needle-shaped rutile inclusions, rutilated quartz crystals are the answer. Quartz crystals in igneous rocks occasionally show an onion-like internal structure, indicating a pulsating addition of outer layers to the crystals. The formation of new crystals is not inhibited as such, but under conditions of slow growth, larger crystals are favored.
If you're really determined to grow quartz crystals at home, you can grow small crystals by heating silicic acid in a pressure cooker. These crystals are colored with the help of modern heat treatment of certain types of amethyst crystals that can be found naturally in igneous rocks. Because they are usually the last to form and simply fill the remaining gaps in the rock, ideally shaped quartz crystals are rarely seen in a granite, whereas well-formed feldspar crystals can often be found.