Losing 1 stone in 1 week would be quite an accomplishment, especially for a woman...it is possible if you have a lot of weight to lose and fall into the 'obese' category, but it will require a lot of work.
First, adopt a diet of 1,200 calories...
Second, do 1+ hours of cardio daily...
On the final day, do as much cardio as you can....dehydrate yourself to shed off as much water weight as possible...and you may be able to hit that number.
Keep in mind, water weight loss is only temporary though...you tend to lose a lot of water weight your first week of dieting and see large numbers on that first week, so that is your best shot to see a 14 pound loss on the scale.
But...really, and I think you know this..the best solution is to find a diet plan that is sustainable over the long term and to stop looking for short term quick results.
What is the point of losing 14 pounds/1 stone if you just wind up putting it back on by going back to your old habits again?