it shows the
following part, being a resonator and not a crystal,
There are ceramic resonators and there are crystal resonators, both can be called resonators. And in fact a ceramic resonator could be called a crystal resonator as it's ceramic structure is of a crystalline nature. A quartz
crystal resonator also has (of course) a crystalline structure, and is what most people mean when they say, in overly shorthand fashion, 'crystal'.
Been working with crystal resonators sense the 60s where we would sometimes grind the blanks in tooth paste to try and raise it's frequency resonance, or draw with pencil lead to try and lower the frequency. Novice ham operators in the 60s were required to be crystal resonator controlled on their 75 watt maximum morse code transmitters, and not until one upgraded their licence were they free to use a VFO and were therefore no longer 'rock bound'.