If you collided with something in the snow and damaged your vehicle then the coverage used would indeed be your collision coverage.

When you damage your own vehicle and need to make an insurance claim to get it repaired you can use your own physical damage coverages of collision or comprehensive. The manner in which the damage occurred will help determine how which coverage will be used.

Comprehensive or "other than collision" covers you your vehicle, and sometimes other vehicles you may be driving for losses resulting from incidents other than collision. For example, comprehensive insurance covers damage to your car if it is stolen; or damaged by flood, fire, or animals. Coverage is limited to the terms and conditions contained in the policy.

Collision covers damage to your car when your car hits, or is hit by, another vehicle, or other object. This type of coverage is again limited to the terms and conditions contained in the policy.

It does not matter if the accident was due to snow or ice but more how the accident occurred whether it would be your comprehensive or collision coverage that was used for the claim. If due to the snow or ice on the roadway you slid off the road and collided with a guardrail, pole or another car this would be an accident claim to place under your collision coverage. If instead the snow did not allow you enough stopping distance and you hit a deer then this would be covered under the comprehensive portion of your policy.

By reading the terms of your policy and speaking with your insurance agent or claims adjuster you should be able to get more information on why your specific situation is classified as a collision claim.