These magical devices are some of the most ubiquitous in existence. They are the one of the first items that craftsmen of the arcane learn to create, and among the simplest in construction. Simply put, a harmonic lens is a device used to amplify magical power, and to some degree, focus it. They are comparatively weak and very limited in their capabilities. That said, they are one of few universal magical devices - working with virtually any source of magic power. I have seen them used to enhance arcane magic, aid in alchemic, focus psionic power, or even help an individual guide their own dreams! For these reasons, they are often used as a basic component of far more intricate and powerful devices. Many can be found that have long since ceased to function - worn by nobility or others as symbols of status.