Potion flask

The Potion flask acts as a large vial and can hold up to six doses of potion (including Juju potions and other untradeable potions, such as Overloads) rather than four in the traditional vial, and will shatter upon being emptied of its contents. Potion flasks are made using a glassblowing pipe with robust glass, yielding 100 Crafting experience. Making them requires 89 Crafting (boostable, but not assistable). Flasks cannot be partially filled, or refilled. After a sip of potion has been taken from the flask, it can't be sold in the Grand Exchange, they can however still be traded with other players.

Despite being created entirely of non-tradeable materials, the flask is tradeable, as are any six-dose flasks containing tradeable potions. Because the resources required to craft Robust glass are non-tradeable and have a maximum of 50 available to players daily (or more with the extra ores bonus from Shooting Star), Potion flasks will likely be in short supply as well as high in demand, and it is Jagex's hope that players will find making them profitable. Mining the red sandstone gives 70 exp. If 50 flasks are made, 5000 Crafting exp and 3500 mining exp is gained.

Trivia

 * The Potion flask was announced in the 2012 February Behind the scenes.
 * On the day of release, flasks sold for over 20,000 coins on the grand exchange. This quickly stopped.
 * It is confirmed that being under the effect of the Shooting Stars boost will provide additional Sandstone while mining. This method provides about 5-15 additional sandstone.
 * Using and activating resourceful will also mean the red sandstone will take longer to deplete so that you can get more.
 * These are fun to play 1man1jar with.