(with occasional bursts of orange).
This makes me think that the main problem here is overexposure and the phenomena which causes chroma shift is optical dispersion - which is only noticeable in everyday usage when strong light source is present in the frame (the defect is called flare) or contrast details are placed around image border (chromatic aberration).
The sizes of the spark in different wavelengths are different, the size of spark in blue (short) wavelengths is somewhat bigger than in red (long) wavelengths, and that causes the spark to appear blue for camera when red (long) wave image blows up and becomes white.
The color of the spark in this case is also dependent on how far away the objective of camera is focused: somewhat forward or somewhat backward, and where in the frame the spark is positioned: in the center or close to borders.
This is an example of warm light source which looks pink because of dispersion and overexposure.
P.S. It may also be that the larger image is formed not by short wavelengths but IR wavelengths instead which cheap cameras are known to be more prone to. IR light may have cyan appearance.