The nine-point circle with the Euler line was generalized into the nine-point conic. Through a similar process, due to the analogous properties of the two circles, the Spieker circle was also able to be generalized into the Spieker conic.
The nine-point circle with the Euler line was expanded into the nine-point conic. Through a comparable process, due to the similar properties of the two circles, the Spieker circle was also able to be generalized into the Spieker conic.