Klondex Announces New Open Pit Mineral Resource Estimate at Fire Creek; Total Indicated of 1.1M AuEq Oz and Inferred of 1.1M AuEq Oz

VANCOUVER, BC--(Marketwired - December 21, 2017) - Klondex Mines Ltd. (TSX: KDX)(NYSE American: KLDX) ("Klondex" or the "Company") is pleased to provide an initial open pit Mineral Resource estimate for its Fire Creek mine ("Fire Creek") located in northern Nevada, USA, which incorporates the results from the 2017 open pit surface and underground exploration drill programs. This Mineral Resource estimate is in addition to the Company's previously announced underground Mineral Resources. Klondex plans to provide a complete Mineral Reserve and Resource update, for all sites, during the first quarter of 2018.

Fire Creek Open Pit Mineral Resource Highlights: (See Table 1 and Figures 1-3)

• Total Indicated Mineral Resource estimate of 42.9M tons grading 0.026 AuEq opt (0.88 AuEq g/t) for a total of 1.1M AuEq ounces
• Total Inferred Mineral Resource estimate of 31.7M tons grading 0.035 AuEq opt (1.19 AuEq g/t) for a total of 1.1M AuEq ounces
• This initial Mineral Resource estimate excludes all underground Mineral Resources reported at Fire Creek, however there is potential to mine relatively higher grade underground resources, outside the underground mine plan, from surface
• The open pit mineralization is open to the north, south and west
• The Company will remain focused on mining and further delineating the high grade underground veins while looking for strategic alternatives to advance and develop the bulk tonnage open pit Mineral Resource

Table 1: Fire Creek Open Pit Mineral Resource Estimate
Category	Tons (M)	Au opt	Au g/t	Ag opt	Ag g/t	AuEq opt	AuEq g/t	Au Moz	Ag Moz	AuEq Moz
Indicated	42.9	0.025	0.87	0.055	1.88	0.026	0.88	1.093	2.350	1.105
Inferred	31.7	0.034	1.17	0.091	3.12	0.035	1.19	1.085	2.882	1.101

	1.	Mineral resources are calculated at a gold price of US$1,400 per ounce and a silver price of US$19.83 per ounce.
	2.	Metallurgical recoveries for gold and silver are 65% and 30%, respectively for oxide mineralization and 60% and 25% respectively for mixed mineralization.
	3.	One ounce of gold is equivalent to 183.53 ounces of silver.
	4.	Mineral Resources include 10% dilution and 5% mining losses.
	5.	Cut off grades for the Mineral Resources are 0.01opt AuEq.
	6.	The effective date for the Mineral Resource is November 30, 2017.
	7.	Mineral Resources which are not Mineral Reserves have not yet demonstrated economic viability. The estimate of mineral resources may be materially affected by environmental, permitting, legal, title, taxation, sociopolitical, marketing, or other relevant issues.
	8.	The quantity and grade of reported Inferred Resources in this estimation are uncertain in nature and there has been insufficient exploration to define these Inferred Resources as an Indicated or Measured Mineral Resource and it is uncertain if further exploration will result in upgrading them to an Indicated or Measured Mineral Resource category.
	9.	The Mineral Resources in this press release were estimated using the Canadian Institute of Mining, Metallurgy and Petroleum (CIM), CIM Standards on Mineral Resources and Reserves, Definitions and Guidelines prepared by the CIM Standing Committee on Reserve Definitions and adopted by CIM Council.

Mr. Paul Huet, President and CEO, commented, "The results of this initial open pit drill program are extremely exciting for Klondex. We believe that the addition of these open pit mineral resources has the potential to significantly extend Fire Creek's mine life." Mr. Huet continued, "Fire Creek continues to demonstrate it is a world-class property and we now have data suggesting the underground and open pit potential is robust with the possibility for these resources to significantly expand with our continued district exploration programs. We will continue to maximize the full value of this asset for our shareholders. Management will continue to focus our efforts on the higher grade, underground mineralization while exploring and evaluating strategic alternatives to advance and develop the open pit potential of this asset."