The performance of this ultra-low cost spectroscope is comparable with instruments typically costing £80. It uses a CD or DVD as a reflective diffraction grating and clearly shows Fraunhofer lines in the spectrum arising from natural light and distinctive emission bands from artificial sources such as sodium lamps. Differences between fluorescent lighting tubes - e.g., white light or ‘warm’ light types - can be easily identified by their distinctive emission bands. The spectroscope is made from virtually indestructible polypropylene and supplied in flat pack form – taking about 30 seconds to assemble. It comes with a free CD but can be used with any CD (or a DVD for higher resolution).