Figure [NaN] demonstrates how the particle size of a powder compact influences its optical properties. In a preliminary study, powder compacts have been prepared using amorphous SiO2 (quartz glass) powders with two different particle size distributions, that is, with a d50 of 10 μm and 300 nm, respectively. A more comprehensive study of the particle‐size‐dependent optical properties of ceramic powder compacts will be published elsewhere. In brief: The optical properties of the powder compacts have been measured by employing a Lambda 900 UV/Visible/NIR spectrophotometer from Perkin Elmer. Clearly seen is a change in the relative reflected intensity. While the powder compact made from a SiO2 powder with a d50 of 10 μm reflects almost all intensity over the entire spectral range measured, the powder compact made from the finer powder clearly shows a reflectivity progressively decreasing from 1 μm to 2.5 μm wavelengths. According to the low k value of SiO2 in this wavelength range, a significant portion of the impinging light is transmitting the compact (data are not shown here). Thus, by using even finer SiO2 powders, it will be possible obtaining an appreciable transitivity of SiO2 powder compacts at the technically relevant laser wavelength of 1 μm. In this context, it is worth mentioning that lasers in an output power range of 100 W cw.and emitting at about 2 μm wavelength have emerged on the market recently. The absorbance of the powder compact can be tuned by adding the right portion of highly absorbing material to the initial ceramic powder. As a result, a better control of the sintering process and a faster and more uniform sintering will be achieved.