Horizonte Minerals PLC — Capital/Financing Update 2021

Nov 24, 2021

Cassels

November 24, 2021

Ontario Securities Commission (Principal Regulator)
British Columbia Securities Commission
Alberta Securities Commission
Financial and Consumer Affairs Authority of Saskatchewan
The Manitoba Securities Commission
Financial and Consumer Services Commission, New Brunswick
Nova Scotia Securities Commission
Office of the Superintendent of Securities, Prince Edward Island
Office of the Superintendent of Securities Service Newfoundland and Labrador
Northwest Territories Securities Office
Office of the Superintendent of Securities, Yukon Territory
Nunavut Securities Office

Dear Sirs / Mesdames:

Re: Horizonte Minerals PLC (the "Corporation")

We refer to the prospectus supplement dated November 24, 2021 (the "Supplement") to the short form base shelf prospectus of the Corporation dated October 29, 2021 qualifying the distribution of ordinary shares of the Corporation.

We, as counsel to the Corporation, hereby consent to the references to our firm name on page S-2 of the Supplement and under the heading "Interest of Experts" and to the reference to and use of our opinion under the heading "Eligibility for Investment" in the Supplement.

We confirm that we have read the Supplement and that we have no reason to believe that there are any misrepresentations in the information contained therein that is derived from our opinion referred to above or that is within our knowledge as a result of the services we performed in connection with such opinion.

Yours truly,

"CASSELS BROCK & BLACKWELL LLP"

t: 416 869 5300
f: 416 360 8877
cassels.com
Cassels Brock & Blackwell LLP
Suite 2100, Scotia Plaza, 40 King Street West
Toronto, ON M5H 3C2 Canada