Largely propelled by the burgeoning spa industry, hot stone massage is practiced by an increasing number of massage therapists around the world. Although many hot stone massage therapists purchase a set of stones from a distributor, it is possible to find them in the natural environment. Whether buying the stones or searching for them on your own, therapists practicing this specialty should know about the different properties rocks can have – and the desired characteristics for a therapeutic hot stone massage.

About Hot Stone Massage

A variation of bodywork, hot stone massage involves the use of warm, smooth, flat stones during a session. There are two primary uses for the stones:

  1. When carefully positioned on top of or underneath a client, stones exert pressure while transmitting heat for an extended period of time.
  2. When used as a tool by the therapist, stones can reduce demand on the practitioner’s body by transmitting force to tissue-specific locations.

There are many variations in hot stone techniques, including recruitment of the stones for stimulation or relaxation of the body’s:

  • Meridians
  • Chakras
  • Lymphatic system
  • Central nervous system
  • Muscular system

Regardless of these different uses, specific geological properties are desired in each rock when being used for hot stone massage.

Types of Stones

Geologists explain that rock is a naturally occurring compound of minerals. Since they are classified by their composition and texture, the three general types of rocks include:

  1. Igneous – Igneous rocks are formed when molten magma cools. Basalt stones are an example of igneous rocks.
  2. Sedimentary – Sedimentary rocks are formed by little pieces of earth that have been eroded over time. As eroded earth layers on top of each other, the pressure slowly turns the earth into rock.
  3. Metamorphic – Originally igneous or sedimentary rocks, metamorphic rocks are rocks that have morphed into another kind of rock. When rocks are under tons of pressure, heat builds up which causes them to change. Under close examination, metamorphic rock contains flattened grains.

In general, the types of rocks most desired for hot stone massage are igneous or metamorphic. This is because igneous and metamorphic rocks are generally rich in iron ore, allowing them to absorb and retain heat for a longer period of time than stones with little iron. Of these two categories, basalt stones (igneous) are the most highly regarded due to their smooth texture and unparalleled iron content.

Besides choosing igneous or metamorphic stones, instructor of the Institute’s Stone Massage home study course, Carollanne Crichton, advises the following four criteria to help select massage stones:

  1. Stone Composition – Look and feel for stone density to determine how much mineral ore is present. Since ore is a heat and geomagnetic conductor, choose heavier stones for better heat conductivity.
  2. Stone Shape – Keep in mind your needs for the shape of each stone you select. When placing stones underneath a person in a layout foundation or resting on top of them, those stones must fit the body’s natural contours comfortably. In general, smooth edges and a relatively flat dimension help keep the stones in place without discomfort.
  3. Stone Texture – Although smooth and polished stones might be assumed best for hot stone massage, this is not always the case. Besides avoiding jagged edges, stones with some texture can be beneficial for exerting stimulation to lymphatic fluid during stone-assisted massage strokes.
  4. Stone Size – Differently sized stones will have different levels of weight, traction and heat retention. Since larger stones have a greater capacity for these three properties, seek the largest rocks that will comfortably and securely fit the intended location.

One of the few branches of bodywork that requires an additional set of tools, hot stone massage is growing in popularity. Since they are a product of our natural environment, rocks can have so many different properties. Being able to differentiate between the three types of rock and evaluating stones based on Crichton’s selection criteria equips therapists to choose their tools for the best possible therapeutic outcome.

Recommended Study:

Stone Massage

References:, Hot Stone Massage, Cathy Wong, About, Inc., 2008., Rock (geology), Wikimedia Foundation Inc., 2008., Making Your Own Hot Stone Massage Kit, Fiona Bryland, March 2008., How Igneus Rock is Formed, Rock Hounds, 2008., How Metamorphic Rock is Formed, Rock Hounds, 2008., How Sedimentary Rock is Formed, Rock Hounds, 2008., About Our Stones, Stone Temple Institute, 2008., Why Hot Stone Massage?,, 2008.