Table 1: Two types of comets as defined by Gehrz & Ney (1992) in the view of later papers.

Reference	Type I	Type II
Gehrz & Ney (1992):	no superheat	color temperature excess
	no or weak silicate feature	strong silicate feature
	large dust grains	small dust grains
Chernova et al. (1993):	gas-rich	dust-rich
	(as apparent in visual wavelength range)
	low polarization?	high polarization
Levasseur-Regourd et al. (1996):	low polarization	high polarization
This paper:	high polarization	high polarization