Foreign invested companies cannot hold a permit to exploit industrial minerals.
"2. Interpretation
 (1) In this Act, unless the context otherwise requires-[...]
"industrial mineral" means barite, basalt, clay, dolomite, feldspar, granite, gravel, gypsum, laterite, limestone, mica, magnesite, marble, phosphate, rock, sand, sandstone, slate and talc, when used for agricultural, building, road making or industrial purposes and such other minerals as may be prescribed in the regulations to be industrial minerals;
"mineral" means any substance, whether in solid, liquid or gaseous form, occurring naturally in or on the earth, formed by or subject to a geological process, but excluding petroleum as defined in section 2 of the Petroleum (Exploration and Production) Act (Cap. 67:01), and public and private water when used for a primary, secondary or tertiary use, as defined in theWater Act (Cap. 34:01);
"mineral concession" means a prospecting licence, a retention licence, a mining licence, or a minerals permit;
[...]
53. Permits for industrial minerals
 (1) Subject to the provisions of subsection (2), a minerals permit to exploit industrial minerals shall not be granted to a person who is not a citizen of Botswana.
 (2) The Minister may exempt any person from the provisions of subsection (1) if he is satisfied that-
 (a) it is in the public interest that a minerals permit to exploit industrial minerals should be granted to such person; or
 (b) the permit applied for is in respect of industrial minerals required for specific works and the applicant has given an undertaking that the minerals concerned will not be sold or otherwise disposed of for profit.
 (3) In this section "citizen of Botswana" means-
 (a) in relation to an individual, an individual who is a citizen of Botswana;
 (b) in relation to a partnership or association of individuals, a partnership or association which is composed exclusively of individuals who are citizens of Botswana; and
 (c) in relation to a corporate body, a corporate body which is incorporated under the Companies Act-
 (i) which is certified by the Minister to be controlled by the Government, or  (ii) whose directors and beneficial shareholders are all citizens of Botswana.[...]" (Mines and Minerals Act, 1999 (Chapter 66:01))
Mines and Minerals Act, 1999 (Chapter 66:01)
[<a href="http://extwprlegs1.fao.org/docs/pdf/bot50854.pdf">Act</a>]