CFR › Title 26 › Part 50Part 50 — Regulations Relating to the Tax Imposed with Respect to Certain Hydraulic Mining§ 50.1— Introduction.§ 50.2— Scope of regulations.§ 50.3— General definitions and use of terms.§ 50.4— Rates of tax.§ 50.5— Liability for the tax.§ 50.6— Ascertainment of quantity mined.§ 50.7— Returns.§ 50.8— Due date and place for filing returns and paying tax.