<?xml version="1.0" encoding="us-ascii"?><InstanceReport xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"><Version>2.4.0.8</Version><ReportLongName>0010 - Disclosure - 5. MINING RIGHTS</ReportLongName><DisplayLabelColumn>true</DisplayLabelColumn><ShowElementNames>false</ShowElementNames><RoundingOption /><HasEmbeddedReports>false</HasEmbeddedReports><Columns><Column FlagID="0"><Id>1</Id><IsAbstractGroupTitle>false</IsAbstractGroupTitle><LabelSeparator>

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</LabelSeparator><Level>2</Level><ElementName>us-gaap_IntangibleAssetsDisclosureTextBlock</ElementName><ElementPrefix>us-gaap_</ElementPrefix><IsBaseElement>true</IsBaseElement><BalanceType>na</BalanceType><PeriodType>duration</PeriodType><IsReportTitle>false</IsReportTitle><IsSegmentTitle>false</IsSegmentTitle><IsCalendarTitle>false</IsCalendarTitle><IsEquityPrevioslyReportedAsRow>false</IsEquityPrevioslyReportedAsRow><IsEquityAdjustmentRow>false</IsEquityAdjustmentRow><IsBeginningBalance>false</IsBeginningBalance><IsEndingBalance>false</IsEndingBalance><IsReverseSign>false</IsReverseSign><FootnoteIndexer /><Cells><Cell FlagID="0" ContextID="Context_3ME_30-Apr-2013" UnitID=""><Id>1</Id><IsNumeric>false</IsNumeric><IsRatio>false</IsRatio><DisplayZeroAsNone>false</DisplayZeroAsNone><NumericAmount>0</NumericAmount><RoundedNumericAmount>0</RoundedNumericAmount><NonNumbericText>&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;As of July 31, 2013 and January 31, 2013,
the Company had $91,250 of mineral rights related to the AuroTellurio Property, discussed below.&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0; text-align: justify; text-indent: 0.5in"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;On February 11, 2011, the Company entered
into a property option agreement (the &amp;#147;AuroTellurio Option Agreement&amp;#148;) with Mexivada Mining Corp. (&amp;#147;Mexivada&amp;#148;)
to acquire up to an 80% interest in Mexivada&amp;#146;s concessions comprising its AuroTellurio tellurium-gold-silver property (the
&amp;#147;La Viuda Concessions,&amp;#148; the &amp;#147;AuroTellurio Property,&amp;#148; or the &amp;#147;Property&amp;#148;) in Mexico.&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0; text-align: justify; text-indent: 0.5in"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;Under the terms of the AuroTellurio Option
Agreement, the Company will acquire up to an 80% legal and beneficial ownership interest in the AuroTellurio Property by making
certain cash payments and share issuances to Mexivada and incurring certain exploration expenditures on the Property. See Note
11 for the Company&amp;#146;s commitments under the AuroTellurio Option Agreement.&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0; text-align: justify; text-indent: 0.5in"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;Mexivada and its Mexican subsidiary hold
only the mineral rights in the AuroTellurio Property, which rights were granted by the government of Mexico. Neither Mexivada nor
its Mexican subsidiary owns the real property rights to the land underlying the La Viuda Concessions. Prior to the first closing
under the AuroTellurio Option Agreement on August 4, 2011, the Company obtained a surface rights agreement with the landowner on
whose property the La Viuda Concessions are located to conduct its mineral exploration program. The agreement became effective
June 17, 2011, runs for a term of 12 months, and may be extended for two additional years under the same terms. The Company will
pay the land owner $14,400 for each year in which the Company carries out exploration work on this land. In June 2012, the agreement
was extended for an additional year.&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0; text-align: justify; text-indent: 0.5in"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;On August 4, 2011, the Company conducted
the first closing under the AuroTellurio Option Agreement. The purchase price for the first closing was $30,000 in cash and 250,000
common shares, fair valued at $17,500 based on the market price on the date of issuance. The $30,000 in cash includes the $20,000
deposits paid to Mexivada in December 2010 in connection with signing the binding offer letter agreement, which provided the Company
with additional time to perform its due diligence, raise financing, and prepare a definite purchase agreement. At the closing,
the Company paid the remaining $10,000 cash and issued the 250,000 common shares.&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0; text-align: justify; text-indent: 0.5in"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;In exchange, the Company received from
Mexivada four fully executed title deeds, each transferring to the Company a twenty percent (20%) interest in the La Viuda Concessions
comprising the AuroTellurio Property, to be held in escrow by the Company's counsel until fully vested in accordance with their
terms. If the Company defaults on its commitments under the AuroTellurio Option Agreement or otherwise determines not to proceed
with the acquisition of the AuroTellurio Property, all unvested interests and related title deeds in the AuroTellurio Property
will be returned to Mexivada.&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0; text-align: justify; text-indent: 0.5in"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;On the first anniversary of the closing,
the first $750,000 requirement per year was reached by the Company, per the AuroTellurio Option Agreement (Note 11). The Company
made a payment of $40,000 on August 10, 2012 and issued 250,000 shares on August 28, 2012, fair valued at $3,750, based on the
market price on the date of issuance. Having met all the required conditions, the first 20% interest in the La Viuda Concessions
has vested in the Company as of August 28, 2012.&lt;/p&gt;</NonNumbericText><FootnoteIndexer /><CurrencyCode /><CurrencySymbol /><IsIndependantCurrency>false</IsIndependantCurrency><ShowCurrencySymbol>false</ShowCurrencySymbol><DisplayDateInUSFormat>false</DisplayDateInUSFormat></Cell></Cells><ElementDataType>nonnum:textBlockItemType</ElementDataType><SimpleDataType>na</SimpleDataType><ElementDefenition>The entire disclosure for all or part of the information related to intangible assets.</ElementDefenition><ElementReferences>Reference 1: http://www.xbrl.org/2003/role/presentationRef

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