Few are fortunate enough to come across the tears of the very goddess who created our world... but those who are lucky enough to acquire a Tear of the Goddess may take pleasure in a significant boost of mana points and mana points regeneration.
Selling Tear of the Goddess and its upgrades removes the bonus mana. There is a small window of time during which Tear of the Goddess or related items can be re-bought while still retaining the bonus mana stacks. In addition, while any Tear of the Goddess or related item is held, the bonus mana stacks are retained, even if the original item used to gain the stacks is sold.
Assuming a charge is gained every 4 seconds, the 750-mana unique passive takes 11 minutes and 7 seconds to max.
The bonus mana does stack with Seraph's Embrace and Muramana. This is due to the fully formed Seraph's Embrace and Muramana not having the Mana Charge passive. The tear starts at 0 however, and must be charged again. Useful in mana stacking strategies such as Muramana Ryze.
Tear of the Goddess combines excellently with champions with spammable abilities or abilities with low costs that constantly consume mana (e.g. Singed'sPoison Trail or Karthus'sLay Waste), ideally bringing a fully filled Tear of the Goddess at the 20 minute mark.