Defending champion Bright fell just 0.25 short of that benchmark, while 30-year-old Clark posted a score of 90.75.
Meanwhile, finishing just off the podium, by a margin of just 0.25 points, was the Turin 2006 gold medallist Hannah Teter, who led after the first run with her score of 90.50.
In a day of twists and turns, it was a remarkable climax to the competition for Farrington, who had failed to make the final directly from the heats, needing a “second-chance” semi-final to progress, but produced a stunning second run to score 91.75, after a first run score of 85.75 left her almost five points behind compatriot Tetter.
As for Bright and Clark, both failed to complete their first runs in the final, setting up a tense finale, I which all of the 2010 and 2002 champions responded to the pressure by upping the ante and throwing down their big moves to impress the judges.
Clark posted 90.75 in her second run to move into gold medal position, but it was short-lived as Bright then stepped up to produce her most taxing routine of the day, which was rewarded with 91.50 and first place.
With the bar raised, Farrington slipped into gear, and delivered a flawless run, which included enough difficulty to merit the day’s top score of 91.75.
Only Teter could dislodge her from pole position now. The 2006 Olympic champion made a Monte Carlo-or-bust attempt to clinch another gold with an outlandish 1080 turn, stalled, and had to rely on her first run score, which was enough to give her fourth place.
It was a magnificent result for Farrington, who now joins her three rivals as an Olympic half-pipe gold medallist, underlining the status of this exciting discipline as one of the most fiercely contested on the programme.