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Cypress Development to Start Pilot Plant Program FOR Clayton Valley Lithium Project, Nevada

Metallurgy & Processing

NEWS RELEASE TSXV: CYP | OTCQB: CYDVF

CYPRESS DEVELOPMENT TO START PILOT PLANT PROGRAM

FOR CLAYTON VALLEY LITHIUM PROJECT, NEVADA

October 13, 2021 - Vancouver, Canada - Cypress Development Corp. (TSXV: CYP) ( OTCQB: CYDVF)

(Frankfurt: C1Z1) (“Cypress” or “the Company”) is pleased to report that the assembly of the pilot plant

for the Company’s 100% -owned Clayton Valley Lithium Project in Nevada is complete. The pilot plant is

located at a metallurgical facility approximately 100 miles south of the project. P urchasing of items for

the pilot plant began in March and work progressed through the summer. With assembly and operational

testing of component equipment finished, test extraction of lithium from the project’s sample material

will begin next week. The pilot plant will utilize chloride-based leaching combined with the Chemionex—

Lionex process for direct lithium extraction (DLE), as described in previous announcements.

“The completion of the pilot plant represents a significant milestone and marks the culmination of months

of work by Cypress , our consultants , and contractors ” stated Bill Willoughby, President and CEO of

Cypress. “This work, under the direction of Continental Metallurgical Services and supported by the

management and personnel of del Sol Refining , Inc., has resulted in a pilot plant that embodies the

research that went into our process flowsheet. The testing ahead will be one of the larger piloting efforts

to extract lithium from clay in the world, and the only one based on a chloride approach to leaching. While

the ultimate goal is to demonstrate the production of lithium hydroxide from our claystone resource on

a larger scale, the results from the various areas within the plant, from leaching and tailings handling, to

solution treatment and recycling, chemical usage and water balance, will provide the data necessary to

carry the project forward to the feasibility level."

The Company’s pilot plant is configured to use chloride-based leaching to liberate the lithium from the

project’s claystone. This was based on results from an internal scoping study completed in January 2021,

which determined additional benefits in the areas of econo mics, process, and the environment when

using a chloride-based rather than a sulphate-based leaching process . The sulphate -based process

remains a viable alternative as detailed in the project’s Pre-Feasibility Study (PFS, effective Date August

5, 2020 and amended March 15, 2021).

Pilot Plant Program Objectives

The pilot plant is intended to confirm the extraction of lithium from the Company's Clayton Valley Lithium

Project, in following the recommendations outlined in the Company's PFS.

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There are four main sections in the pilot plant: leaching, tailings handling, pregnant leach solution (PLS)

treatment and the Chemionex —Lionex DLE process area . Two additional processing steps will be

conducted off-site at NORAM Engineering and Construction, Ltd's B.C. Research Laboratory in Richmond,

Canada; these steps w ill take the concentrated lithium solution and a portion of the depleted solution

following DLE for the production of lithium hydroxide and the generation of hydrochloric acid and sodium

hydroxide.

Each section in the pilot plant has specific objectives. The leaching section will work to improve leach

conditions and confirm lithium extraction into PLS. Testing of various feed size and grade of the claystone,

reagent mixtures, and water balance will aid in optimization at scale.

The tailings handling section will utilize a counter current decantation arrangement of thickener settlers

and flocculant mixing, with the objective of determining materials handling, moisture content and water

consumption. Testing in this stage will provide key information for water requirements and design of

tailings facilities.

The PLS treatment section will remove impurities prior to introduction into the DLE process through two-

stage neutralization and filtration, a tertiary stage will follow the DLE process prior to recycling of solution

back to leaching.

The DLE section consists of Chemionex's—Lionex DLE technology and will test compatibility of the PLS to

be further concentrated with this process. Cypress was granted an option, upon completion of the pilot

plant program, to license this process for commercial use at its project.

The final two steps will be conducted by NORAM Engineering, these will treat the concentrated lithium

solution from the DLE portion of the pilot plant to produce lithium hydroxide and test the stripped leach

solution for compatibility for recycling to the leaching section of the plant.

Pilot Plant Photos

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About Cypress Development Corp

Cypress Development Corp. is a Canadian advanced stage lithium exploration company, focused on

developing its 100%-owned Clayton Valley Lithium Project in Nevada, USA. Work completed by Cypress

led to the discovery of a world-class resource of lithium-bearing claystone adjacent to the Albemarle Silver

Peak mine, North America's only lithium brine operation. The results of a positive Pre-Feasibility Study for

the Clayton Valley Lithium Project were announced by Cypress Development in August 2020. Cypress

Development trades on the TSX Venture Exchange under the symbol CYP, and on the OTCQB under the

symbol CYDVF.

ON BEHALF OF CYPRESS DEVELOPMENT CORP.

WILLIAM WILLOUGHBY, PhD., PE

President & Chief Executive Officer

For further information, please contact:

Spiros Cacos | Vice President, Investor Relations

Direct: +1 604 764 1851 | Toll Free: 1 800 567 8181 | Email [email protected]

www.cypressdevelopmentcorp.com

NEITHER THE TSX VENTURE EXCHANGE NOR ITS REGULATION SERVICES PROVIDER ACCEPTS

RESPONSIBILITY FOR THE ADEQUACY OR ACCURACY OF THE CONTENT OF THIS NEWS RELEASE.

Cautionary Note Regarding Forward-Looking Statements

This release includes certain statements that may be deemed to be "forward -looking statements". Forward-looking

statements are subject to risks, uncertainties and assumptions and are identified by words such as “ex pects,”

“estimates,” “projects,” “anticipates,” “believes,” “could,” “scheduled,” and other similar words. All statements in

this release, other than statements of historical facts, that address events or developments that management of the

Company expects, are forward -looking statements. Although management believes the expectations expressed in

such forward -looking statements are based on reasonable assumptions, such statements are not guarantees of

future performance, and actual results or develop ments may differ materially from those in the forward -looking

statements. The Company undertakes no obligation to update these forward -looking statements if management's

beliefs, estimates or opinions, or other factors, should change. Factors that could ca use actual results to differ

materially from those in forward-looking statements, include market prices, exploration, and development successes,

continued availability of capital and financing, and general economic, market or business conditions. Please se e the

public filings of the Company at www.sedar.com for further information.