Now that herb prices are coming down a bit I decided to do a massive ink/glyph making session to sell on the AH. Since this was my first large scale glyph making session since Cataclysm I decided to get 1,000 of each herb and record what kind of inks I got so that I can know what price I should set my snatch list to buy the herbs in the future. I managed to get most herbs with the one exception of Heartblossom. Heartblossom is still way crazy in price on my server and the supply is very limited - so I decided to forgo this one herb.
Here is the list with how many inks (NOT pigment or embers) per stack of twenty:
Cinderbloom - 4.96 Blackfallow Ink per stack and .46 Inferno Ink per stack
Azshara's Veil - 4.96 Blackfallow Ink per stack and .62 Inferno Ink per stack
Stormvine - 4.92 Blackfallow Ink per stack and .62 Inferno Ink per stack
Whiptail - 6.06 Blackfallow Ink per stack and .98 Inferno Ink per stack
Twilight Jasmine - 5.88 Blackfallow Ink per stack and .98 Inferno Ink per stack
I'm not a statistician but it looks like Azhara's Veil and Stormvine offer the same amount of ink per stack. Cinderbloom is similar but seems to offer a little less Inferno Ink and Whiptail seems to offer a little more Blackfallow ink than Whiptail (this could just be margin of error though).
What should you do with these numbers? Simple. If you are an inscriptionist you can use these numbers to determine at what price you should buy the herb. To do this simply determine the price that inks sell for on your server (NOTE: I do not recommend using what your auctioneer data says. Prices have been dropping since Cataclysm came out so the market price in Auctioneer is probably a bit higher than they are selling for now. Try selling some inks to determine a price that you can sell at instead). Once you have the price of the inks the formula you should use to determine the price of a stack of herbs is:
(Lowest price you will sell Blackfallow ink for *number if Blackfallow ink per stack) + (Lowest price you will sell Inferno ink for * number of Inferno ink per stack)
If you want the price per herb (and not per stack) simply divide the answer by 20.
This gives you your breakeven price (actually a bit under due to AH fees). To determine what you should buy at simply multiply the price by the discount you want to buy at (such as 70% or .7)
This also tells you what price you will sell inks for. When you are choosing to make glyphs you should only make the glyphs that would sell for more than the inks - otherwise it is just better to sell the inks.
Lowest price I will sell one Blackfallow ink for on my server: 10g
Lowest price I will sell on Inferno ink for on my server: 100g
Breakeven price for Twilight Jasmine for me is:
(10 * 5.88) + (100*.98) = 156. 8 gold a stack
I want to make a profit on these so I then multiply it by .8 for a total of 125.44 gold a stack.
So I will buy Twilight Jasmine for 125 gold a stack. Once I convert it into inks I will make glyphs that sell for over 30 gold a stack (the price I will sell Blackfallow ink at x 3) and sell the rest of the inks.
Hope this helps you maximize your inscription profits. I'm making well over 5,000 gold a day selling glyphs and inks right now and you can to!