The company said the measured component had increased 1,242%, from 2.6Moz in a 2018 estimate to 34.9Moz.
The total measured and indicated resource had increased to 44.4Moz, out of 4.9 million tonnes grading 282g/t.
Aya has set an exploration target for Zgounder at depth and along lateral extensions of 20-60Moz.
"In addition to enhancing our understanding of the Zgounder property, this first mineral resource update in several years demonstrates the premium quality of the Zgounder property and positions us well for reaching our objective of 100Moz of silver by year-end 2021," president and CEO Benoit La Salle said.
The update was based on drilling between February 2018 and the end of 2020.
Aya is planning a second update in the fourth quarter, based on 2021 drilling data, with the aim of converting resources into an initial reserve to support an expansion feasibility study.
Zgounder, 15% owned by the Kingdom of Morocco, had produced record quarterly production in December of 407,986oz.
Aya has said it's aiming to increase production to 1Moz annually.
Africa expansion
The company is also expanding its presence in Africa through the acquisition of Algold Resources, with Algold creditors this month approving its proposal to become a subsidiary of Aya.
Aya had become the junior's sole secured creditor in January.
La Salle had founded Algold.
Algold said it believed the proposal and reorganisation of share capital was in the best interests of stakeholders to allow the development of its Tijirit gold project in Mauritania.
Aya (TSX: AYA) shares closed 2% lower yesterday to C$5.39, near the top of its one-year range and capitalising it at $508.6 million (US$408.5 million).
