for other ideas on the glyph market please follow the link to the free Croda's Inscription Gold Guide
Similarly to Herb prices and as was the case in Wrath of the Lich King, the lowest price ink is normally the new common ink introduced by the new expansion and Cataclysm is no exception. Hence, for us Scribes the lowest price ink today is normally the Blackfallow ink.
That should be no surprise and follows from the lowest price herbs being Whiptail, Stormvine and Cinderbloom, see my post Herb Prices for Scribes.
However, there are two things to note here.
Firstly, it is almost always cheaper to buy the herbs to mill/craft the Blackfallow inks. That makes sense – the only people that can craft inks are Scribes and the only people that can use Inks are Scribes. Therefore, any Scribe posting inks to sell is clearly looking to make a profit.
The likely buyers of Blackfallow inks are:
1. new Scribes levelling up
2. exisiting Scribes that are heavily into the Fortune Card business and so need a high supply of Blackfallow ink that can not be met by the supply of herbs on the Auction House
3. where the Scribe does not have the time to mill the herbs – milling herbs is time consuming and can not be done automatically and afk unlike crafting inks from pigments.
On my server, the Blackfallow inks typically sell for 5.5gold each but never falls below 5gold and often rises to nearer 10gold. See my post Herb Prices for Scribes which explains how buying Whiptail at 1 to 1.5gold each and Stormvine/Cinderbloom at 1gold each means that my crafting cost of each Blackfallow ink is 3.33 to 5.0gold each.
Secondly, there are often times when the pre-Cataclysm inks come onto the market at below the crafting price of 5gold. At these times i buy all those inks out and store them for future crafting.
Again, it is worth having all the inks on your snatch list and just going through them once per day.