Avalon Advanced Materials Inc.(TSX: AVL) (OTCQX: AVLNF) ("Avalon" or the "Company") is pleased to announce final assays from the 2022-2023 drilling program at the Company's flagship Separation Rapids Lithium Project, confirming potential to significantly expand its lithium resource at depth. New significant intercepts shown below are from three of the four final drill holes.

• SR23-85: 1.56% Li2O over 47.71 metres ("m")
• SR23-91: 1.06% Li2O over 10.38m and 1.66% Li2O over 7.01m and 1.36% Li2O over 10.61m
• SR23-92: 1.47% Li2O over 3.42m and 1.14% Li2O over 4.35m and 1.49% Li2O over 4.52m

The assays for drill hole SR23-93 (the fourth hole) have confirmed the petalite mineralization to 566-metre depth increasing the potential depth of the deposit by 80%. The drilling has also confirmed that the deposit is open to the east and west, and to depth, over a 300-strike length, with similar grades to the current mineral resource estimate, supporting a conceptual target to double the size of the deposit through future drilling.

"These drill results truly demonstrate what our team has always believed - the resource at Separation Rapids is potentially much larger than what is currently understood," commented Rickardo Welyhorsky, Chief Operating Officer at Avalon. "I am extremely excited to begin the next drilling program to reveal its true potential."

Drilling Program Final Assay Details

The 2022-2023 drill program consisted of 12 drill holes on the existing resource and one vertical drill hole on the centre of the deposit; all 13 holes totalled 4,179m and was designed to examine the potential to expand mineralization to the east and west as well as the depth extent.

Hole SR23-85 (see Figure 1) was one of six targeting either gaps in existing drilling (for 85) or below the current mineral resource estimate, with hole SR23-85 intercepting 1.56% Li2O over 47.7m (estimated true width). As a result, all six holes (SR23-81 to SR23-86) confirm that the deposit is open to depth. All drill holes will be used to update the existing mineral resource estimate, which is currently underway.

Drill hole SR23-93 was drilled vertically to test the depth extent of the deposit (see Figure 2). This hole was terminated at 570m due to weather constraint and the start of early spring breakup. SR23-93 assays returned 1.51% Li2O over 565m (drilled width) confirming the previous report of visual petalite mineralization to depth. This extends the depth of the deposit by 249m from the previously reported deepest intercept at 315m (drilled in 2017) below surface. The grade of the lower half of hole SR23-93 returned 1.48% Li2O over 244.45m (from 321.6m to 566.10m) (see Table 1), which indicates that the mineralization continues at a virtually identical grade to the current mineral resource estimate.

The two holes (SR23-91 and SR23-92) that were drilled in a gap on the western part of the deposit have confirmed the extension and openness of the deposit to the west with intercepts of cumulative about 27m (estimated true width) in hole SR23-91 and cumulative 12 metres in hole SR23-92. They have also, similar to hole SR23-85, potentially improved and expanded the mineralized area.

All drill hole data has been brought into Avalon's database and resource block model in order to develop an independent updated resource estimate for the deposit.

"As a consequence of our refreshed strategic plan, we are delivering on key milestones and accelerating developments at Separation Rapids," noted Zeeshan Syed, President of Avalon. "Ontario continues to be well positioned as an international economic hub within the critical minerals value chain and Avalon is poised for growth to help support that important mandate."

Future Drilling at Separation Rapids

The recent drill program indicating the significant resource expansion potential is an encouragement for very significant future drilling program in order to both increase the inferred resources and upgrade inferred and indicated resources to indicated and measured categories. Such a program may be between 10,000m and 30,000m. The results of the recent program suggest a conceptual exploration target of doubling the existing resource estimate at similar lithium grades. This may be between 15 and 20 million tonnes at 1.2 to 1.6% Li2O. At present there is insufficient drilling below the recent holes SR23-81 to SR23-92 to delineate a resource and it is uncertain that a deeper resource will be delineated.

This news release was reviewed by the Dr. Bill Mercer, P. Geo. (ON). Dr. Mercer is a qualified person for the purposes of National Instrument 43-101, who has reviewed and approved the technical information included in this news release.

About Avalon Advanced Materials Inc.

Avalon Advanced Materials Inc. is a Canadian mineral development company specializing in niche market metals and minerals with growing demand in new technology. The Company has three advanced stage projects, all 100%-owned, providing investors with exposure to lithium, tin and indium, as well as rare earth elements, tantalum, niobium, and zirconium. Avalon is currently focusing on its Separation Rapids Lithium Project, Kenora, ON and its East Kemptville Tin-Indium Project, Yarmouth, NS. Social responsibility and environmental stewardship are corporate cornerstones.

For questions and feedback, please e-mail the Company at ir@AvalonAM.com, or phone Zeeshan Syed, President at 416-364-4938.