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Cypress Development Confirms Positive Metallurgy for Clayton Valley Lithium Project in Nevada

Metallurgy & Processing

Suite 1610 - 777 Dunsmuir Street, Vancouver, BC, Canada, V7Y 1K4

www.cypressdevelopmentcorp.com

TSX Venture Exchange Symbol: CYP

Email: [email protected]

Telephone: (604) 687-3376

Facsimile: (604) 687-3119

NEWS RELEASE

February 26, 2019

Cypress Development Confirms Positive Metallurgy for Clayton Valley

Lithium Project in Nevada

Vancouver, BC - Cypress Development Corp. (TSX-V: CYP) (OTCQB: CYDVF)

(Frankfurt: C1Z1) (“Cypress” or the “Company”) is pleased to report the completion of

the first phase of metallurgical testing in the prefeasibility study (PFS) on the

Company’s 100% held Clayton Valley Lithium Project in Nevada. The testing was

successful in confirming the range of parameters used in the 2018 Preliminary

Economic Assessment (PEA). The results demonstrate lithium extractions of 75 to

83% and sulfuric acid consumptions ranging from 85 to 132 kg/t.

Following the release of the PEA in October 2018, metallurgical testing continued and

is ongoing at Continental Metallurgical Services (CMS) in Butte, Montana. CMS

completed over 75 individual leach tests representing more than 250 laboratory hours

in leaching composite sample material from the project. The objective of the program

was to simulate the leaching portion of the process flowsheet from the PEA, which

consists of agitated tank leaching. The initial tests were single -stage leaching at

specific temperatures, times, and percent-solids levels. The tests then progressed to

multiple-stage leaching using variable acid conditions and residence time, simulating

the leach process from tailings -wash through to final pregnant leach solution (PLS).

Tests were conducted at a lower range of temperatures than the 70 to 90 ⁰ C range

assumed in the PEA. Residence time in the primary leach stage was from 1 to 4 hours,

comparable to the 2 -hour time assumed in the PEA. Recoveries of lithium were

consistently achieved and optimized in the range of 75 to 83% for varying sets of leach

conditions.

This testing was conducted on bulk composites prepared from property-wide drill cores

which were also used in the 2018 check assay program. Further leach testing will be

conducted on samples collected from within the planned mine area in the PFS. The

timeline for these additional tests is dependent upon additional drilling, which was

delayed by various factors. However, to expedite testing for the next phase, assay

reject material from three drill holes, GCH -2, DCH -15 and DCH -17, was used to

prepare 13 composite samples representing the major clay units encountered within

the planned mine area. In addition to the testing on these samples, scope for further

optimization of the leaching process remains. To help accelerate the program, the

Company provided CMS with an ICP unit for its use in assaying at CMS’s lab. All final

assays for the solids and solutions are confirmed by ALS-Chemex.

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While these steps were time-consuming, the focus for the remaining work for the PFS

is not further optimization of leaching, but to demonstrate lithium production from the

PLS into a saleable form. In the PEA process flowsheet, this is accomplished by

purification, evaporation and crystall ization steps. CMS completed a successful

demonstration in the first phase by purifying a 10-liter sample of leachate grading 110

parts per million (ppm) lithium and concentrating it to over 4,000 ppm lithium via

evaporation. The resulting concentrated sol ution contained only negligible levels of

magnesium and other impurities. Purification, evaporation and crystallization remains

the base case assumption for the PFS and will be confirmed in phase two of testing.

Alternative methods for lithium production w ill also be examined, these include ion

exchange (IX) resins and membranes. The Company and CMS have demonstrated

some success using their own in -house IX resin for the extraction of lithium from the

PLS. Cypress has also contracted with a third party for testing of its IX resin.

Cypress CEO Bill Willoughby stated, “We are very pleased with progress on the first

phase. While it was time consuming, the information gained on the behavior of the clay

during leaching is invaluable and represents a huge step forward in our understanding

of the leaching process. With this as a foundation, we are confident in moving forward

to the next phase of testing in the PFS.”

Todd Fayram, MMSA QP #1300, President of Continental Metallurgical Services, LLC,

is the qualified person as defined by National Instrument 43-101 and has approved of

the technical information in this news release.

About Cypress Development Corp.:

Cypress Development Corp. is a publicly traded exploration company focused on

developing the Company's 100%-owned Clayton Valley Lithium Project in Nevada.

Exploration and development by Cypress has discovered a world -class resource of

lithium-bearing claystone adjacent to Albemarle's Silver Peak mine, North America's

only lithium brine operation.

Cypress Development Corp. has approx. 72.5 million shares issued and outstanding.

To find out more about Cypress Development Corp. (TSX -V: CYP), visit our website

at www.cypressdevelopmentcorp.com.

CYPRESS DEVELOPMENT CORP.

“Dr. Bill Willoughby”

WILLIAM WILLOUGHBY, PhD., PE

Chief Executive Officer

For further information contact myself or:

Don Myers

Cypress Development Corp.

Director, Corporate Communications

Telephone: 604-639-3851

Toll Free: 800-567-8181

Facsimile: 604-687-3119

Email: [email protected]

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NEITHER THE TSX VENTURE EXCHANGE NOR ITS REGULATION SERVICES

PROVIDER ACCEPTS RESPONSIBILITY FOR THE ADEQUACY OR ACCURACY OF THE

CONTENT OF THIS NEWS RELEASE.

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

statements". All statements in this release, oth er 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 reas onable assumptions, such statements are not

guarantees of future performance, and actual results or developments may differ materially

from those in the forward-looking statements. The Company undertakes no obligation to update

these forward -looking statem ents if management's beliefs, estimates or opinions, or other

factors, should change. Factors that could cause 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 see the public filings of the Company at www.sedar.com for further

information.