Here is the full list of all 31 Quell Memento achievements. It takes around 8-10 hours to unlock all of the achievements on Windows.
Merge 4 droplets into 1
Emit a beam at least 20 tiles long
Change a bulb 200 times during a level
Switch the battery on 4 times during a level
Travel 200 tiles during a level
Collect every jewel
Watch a full chapter replay
Complete every chapter in perfect moves
Complete every chapter
Collect 24 time pieces
Pass through a seam 40 times
Cross the beams 5 times at once
Get stuck in a loop
Toggle 50 roses
Illuminate blue, gold and red diamonds at the same time
Meet the spirit 3 times
Die on a first move
Complete 3 chapters in perfect moves
Complete 3 chapters
Break an ice block 50 times
Break 10 ice blocks that contain an object
Break a droplet out of an ice block
Collect 30 jewels
Wrap around the edge 30 times
Complete a chapter
Complete a chapter in perfect moves
Collect 50 pearls
Discover a timekeeper level
Complete a stage in perfect moves
Complete a level in under 5 seconds
Collect a jewel