Elune's Tear

I had hoped Orendil's cure would save Relara, but I fear it only slowed the disease running through my child. We must find more powerful medicine! Thankfully, Orendil spoke to me of further remedies to try should his first one fail. Elune's Tear is a type of stone that rests in only one place: the isle on Iris Lake, east of Astranaar. Orendil said the stone will wash away corruption... please, <name>, bring me Elune's Tear and pray it will end my child's sickness!