First Class Metals Confirms High-Grade Lithium and Rubidium at Zigzag Project, Ontario

First Class Metals PLC (LSE: FCM) has reported highly successful drilling results from its Zigzag Project in the Seymour-Falcon corridor, Northwestern Ontario. The inaugural programme not only confirmed significant lithium mineralisation but also revealed elevated rubidium (Rb₂O), caesium, tantalum, and gallium—reinforcing Zigzag as a multi-critical metal asset in a rapidly emerging pegmatite district.

Standout Drill Results

• Lithium (Li₂O) Intersections: ZIG-23-01: 4.3m @ 1.65% Li₂O, incl. 1m @ 2.93% ZIG-23-02: 5.0m @ 1.5% Li₂O, incl. 0.2m @ 5.19% ZIG-23-07: 6.5m @ 1.09% Li₂O, incl. 0.5m @ 2.76%

• Rubidium (Rb₂O) Grades: ZIG-23-02: 5.75m @ 0.21% Rb₂O, incl. 0.3m @ 0.54% (5,400 g/t Rb₂O) ZIG-23-07: 6.6m @ 0.21% Rb₂O, incl. 1.0m @ 0.41% ZIG-23-04: 1.6m @ 0.21% Rb₂O ZIG-23-06: 2.2m @ 0.19% Rb₂O

• Other Critical Metals: Caesium (Cs): up to 480 g/t over 0.45m Tantalum (Ta): up to 624 g/t over 0.45m Gallium (Ga): up to 144 ppm

Why Rubidium Matters

Rubidium, long overshadowed by lithium, is increasingly recognised as a strategic critical metal due to its role in semiconductors, specialised glass, aerospace, and defence technologies. With trading prices reported above US$3,100 per ounce on the Shanghai Metals Market, rubidium offers a potential high-value by-product credit alongside lithium, significantly enhancing project economics.

The grades reported at Zigzag—up to 0.54% Rb₂O (5,400 g/t)—place the project in a globally competitive position, particularly as China currently dominates rubidium supply chains.

Exploration Upside

• The pegmatite-hosted structure remains open along strike and at depth, confirmed by both step-back and scissor holes.

• Geochemical and soil sampling suggest the existence of a second subparallel mineralised structure ~200m south, with indications of a possible third rare-element-bearing trend.

• An Exploration Permit is being drafted to support expanded drilling and stripping programmes.

CEO Commentary

Marc J. Sale, CEO of First Class Metals, commented:

“The results from our first Zigzag drill programme are first class. They not only confirm the potential of the core zone but also highlight the value-added dimension from rubidium, caesium, gallium, and tantalum. Zigzag is rapidly growing into a significant lithium and critical metals play in Ontario.”