All photos and video made with Tesla coil which is absolutely not hurt or use tube. Just to show its hermetic and glow nice Yes, I know that crystal oscillator - quartz resonator is not for light, but for frequency setup of device. But this oscillator is glow like krypton or mercury gas filled tube under high voltage. I think it can be because gold vapor glow or destroying quartz crystal have glow effect. But no other quartz resonators glow, so I cannot explain it for sure. But I have found this explanation - http://www.cdvandt.org/leuchtquarze.htm This also called Sonoluminescence. The Soviet quartz resonators RK-58 1000kHz gold plated were electronic components that were commonly used in Soviet-era electronic devices, such as radios, televisions, and other consumer electronics. A quartz resonator is a device that is used to generate a precise frequency or time base in electronic circuits.The RK-58 quartz resonators had a frequency of 1000kHz (1MHz) and were gold-plated to provide a stable and reliable frequency output. The gold plating helped to protect the quartz crystal from oxidation and other environmental factors that could affect its performance.The RK-58 quartz resonators were known for their high accuracy and stability, which made them a popular choice for use in electronic circuits that required precise frequency control. The quartz crystal in the resonator would vibrate at a specific frequency when an electrical charge was applied, and this vibration would then be used to generate a precise clock signal or other timing reference.While the RK-58 quartz resonators are no longer in production, they remain an interesting piece of Soviet-era technology and a unique part of electronic engineering history. Today, vintage RK-58 quartz resonators can be found in old electronic devices and may be of interest to collectors of vintage electronics or anyone interested in the history of electronic technology. Tube have 0,001328 gr of gold (gold plated contacts)