Note 8 - Stockholders' Equity (Tables)

6 Months Ended

Jun. 30, 2019

Notes Tables

Schedule of Potential Per Share Dividend Amounts Quarterly Price Levels [Table Text Block]

Quarterly average realized silver price per ounce	Quarterly dividend per share	Annualized dividend per share
$30	$0.01	$0.04
$35	$0.02	$0.08
$40	$0.03	$0.12
$45	$0.04	$0.16
$50	$0.05	$0.20