When tested in a standard Colpitts circuit, they show an error up to +/- 3kHz .  The test circuit uses 2 x 180pF capacitors with a trimmer.  The 60pF trimmer pulls the frequency by about 100-500 Hz per MHz

Crystal units 20 to 50 MHz operate as 3rd overtone, those above 50 MHz are 5th overtone. Divide to get fundamental !

FT243 (8 to 12 MHz) and HC49 units (4 to 88 MHz) also available

1.843 MHz HC6 wire ended units strong in harmonics are available in quantity (approx 50). See other items.