Methods and apparatus for laser induced breakdown spectroscopy (LIBS) sample chamber. An apparatus includes a sample chamber, a laser source connected to an excitation optics assembly, the excitation optics assembly connected to a first port on the sample chamber, a collimator assembly connected to a spectrometer, the collimator assembly connected to a second port on the sample chamber, and a first lens tube positioned on the first port and a second lens tube positioned on the second port, the first lens tube protecting the first port connected to the excitation optics assembly and the second lens tube protecting the second port connected to the collimator assembly from particles emitted when a laser pulse from the laser source ablates a surface of a target sample and generates a plasma.