Lossless rip at low bit rate?

I just ripped Coltrane's Blue World, Apple lossless, and the bit rate is lower than I'm used to -- ranges from 411kbps to 464kbps. When I look at other dBpoweramp CD rips, they tend to be around 1000kbps -- though now that I'm looking, I see some albums have higher ranges (Coltrane e.g. The Complete 1961 Village Vanguard Recordings, mostly above 1000kbps) and others lower (Both Directions at Once: The Lost Album, between 500-600kbps).

I'm sure this variation is explained somewhere but my searches have been unsuccessful -- help please?

Are the lower bitrate tracks by any chance mono?

The CD doesn't say, but the liner notes refer to mono -- the properties for one of the tracks say "stereo" but, jeez I feel dumb, how can I tell if it's a "stereo" CD of a mono recording?
Artist Coltrane, John
Title Naima[Take 2]
Album 1964 Blue World
Track 8/8
Disc 1/1
Genre Jazz Saxophone
Year 1964
Rating
Composer
Size 13.57 MB (68% Compressed)
Original Size 41.91 MB
Length 4 minutes 9 seconds
Channels 2 (stereo)
Sample Rate 44.1 KHz;
Sample Size 16 bit
Bit Rate 1,411 kbps
Encoder Apple Lossless (ALAC)
Encoder Settings
Audio Quality Perfect (Lossless)
Contains Album Art, ID Tag [Apple iTunes]
Channel Mapping
File 08 - Naima[Take 2]
Type M4A Audio File (VLC) [.m4a]