Note 11 - Derivative Instruments (Tables)

12 Months Ended

Dec. 31, 2018

Notes Tables

Schedule of Notional Amounts of Outstanding Derivative Positions [Table Text Block]

December 31, 2018

Ounces/pounds under contract (in 000's)

Average price per ounce/pound

Silver

Gold

Zinc

Lead

Silver

Gold

Zinc

Lead

(ounces)

(ounces)

(pounds)

(pounds)

(ounces)

(ounces)

(pounds)

(pounds)

Contracts on provisional sales

2019 settlements

842

4

18,450

2,700

$

14.69

$

1,260

$

1.15

$

0.89

December 31, 2017	Ounces/pounds under contract (in 000's)								Average price per ounce/pound
	Silver		Gold		Zinc		Lead		Silver		Gold		Zinc		Lead
	(ounces)		(ounces)		(pounds)		(pounds)		(ounces)		(ounces)		(pounds)		(pounds)
Contracts on provisional sales
2018 settlements		1,447		5		21,550		4,740	$	16.64	$	1,279	$	1.45	$	1.11
Contracts on forecasted sales
2018 settlements		N/A		N/A		32,187		16,645		N/A		N/A	$	1.29	$	1.06
2019 settlements		N/A		N/A		23,589		18,078		N/A		N/A	$	1.33	$	1.09
2020 settlements		N/A		N/A		3,307		2,866		N/A		N/A	$	1.27	$	1.08