On 23 February an another diamond dust display with odd radius halos occured in Vaala, Finland. Temperature was dropping from -29°C to -24° during my observation.
A parhelic circle and circumzenithal arc were present with nice parhelia. A subsun and subparhelia were also seen as sparkling ice crystals in front of the ground.
Odd radius halos labelled in this enhanced photo are A) a pyramidal heliac arc, B1) upper 24° plate arc, B2) lower 24° plate arc and C) upper 23° plate arc.
The most brightest odd radius halo was 18° halo and in some photos there probably are also 9° upper plate arc and 20° halo. The ice crystal cloud was produced by a local heating plant about 2 km away. More photos can be found here.