Notes: It turns out (perhaps everyone already knew this) that Canadian Tire carries the whole line of Bernardin canning supplies: jars, seals, lids, tongs, funnel, canner, etc. I bought some shorter, wider jars that would better fit in my stock pot. Dr. S and I got a whole flat (12 half-pints) of blackberries at St. Lawrence Market on the weekend. I needed about 8 of those to get the required amount of berries for this jam. Some vanilla sugar and the seeds and pod of another fresh vanilla bean added a nice fragrance to the jam mixture. The pot I used to boil the fruit held only 3 quarts and it very nearly overflowed when it came to a hard boil.
The jam didn't set completely using the regular Certo pectin. I attribute this to not boiling the hot jam hard enough (I was afraid of spills). However, it is extremely tasty, a bit too sweet, yet fragrant with berries and vanilla. My yield was seven 250 mL jars.