Abstract: Novel compositions useful as fluid gelling agents, especially for use in subterranean applications such as drilling fluids, are prepared by reacting an aqueous dispersion of a clay, such as bentonite, with an aqueous gel of a monodispersed mixed metal layered hydroxide of the formula Li.sub.m D.sub.d T(OH).sub.m+2d+3+na) A.sub.a.sup.n, where D is a divalent metal, such as Mg, T is a trivalent metal, such as Al, and A represents other monovalent or polyvalent anions, the formula being described in detail in the disclosure.

Abstract: Novel compositions useful as fluid gelling agents, especially for use in subterranean applications such as drilling fluids, are prepared by reacting an aqueous dispersion of a clay, such as bentonite, with an aqueous gel of a monodispersed mixed metal layered hydroxide of the formula Li.sub.m D.sub.d T(OH).sub.(m+2d+3+na) A.sub.J.sup.n where D is a divalent metal, such as Mg, T is a trivalent metal, such as Al, and A represents other monovalent or polyvalent anions, the formula being described in detail in the disclosure.

Abstract: Novel compositions useful as fluid gelling agents, especially for use in subterranean applications such as drilling fluids, are prepared by reacting an aqueous dispersion of a clay, such as bentonite, with an aqueous gel of a monodispersed mixed metal layered hydroxide of the formula Li.sub.m D.sub.d T(OH).sub.(m+2d+3+na) A.sub.a.sup.n, where D is a divalent metal, such as Mg, T is a trivalent metal, such as Al, and A represents other monovalent or polyvalent anions, the formula being described in detail in the disclosure.

Abstract: Novel compositions useful as fluid gelling agents, especially for use in subterranean applications such as drilling fluids, are prepared by reacting an aqueous dispersion of a clay, such as bentonite, with an aqueous gel of a monodispersed mixed metal layered hydroxide of the formula Li.sub.m D.sub.d T(OH).sub.(m+2d+3+na) A.sub.a.sup.n, where D is a divalent metal, such as Mg, T is a trivalent metal, such as Al, and A represents other monovalent or polyvalent anions, the formula being described in detail in the disclosure.

Abstract: Novel compositions useful as fluid gelling agents, especially for use in subterranean applications such as drilling fluids, are prepared by reacting an aqueous dispersion of a clay, such as bentonite, with an aqueous gel of a monodispersed mixed metal layered hydroxide of the formula Li.sub.m D.sub.d T(OH).sub.(m+2d+3+na) A.sup.n.sub.a.H.sub.2 O, where x is zero or more representing excess water of hydration, where D is a divalent metal, such as Mg, T is a trivalent metal, such as Al, and A represents other monovalent or polyvalent anions, the formula being described in detail in the disclosure.

Abstract: Novel monodispersed crystalline mixed metal layered hydroxide compounds of the general formula are prepared:Li.sub.m D.sub.d T(OH).sub.(m+2d+3+na) A.sub.a.sup.n, where m is an amount from zero to 1; D is a divalent metal; d is the amount of D ions of from zero to 4; T is a trivalent metal; A represents anions or negative-valence radicals of valence n; na is from zero to -3; (m+d) is greater than zero; and (m+2d+3+na) is equal to or greater than 3. The D metal is preferably Mg and the T metal is preferably Al. These compounds are useful as gelling agents which impart beneficial thixotropic properties to various fluids, such as drilling fluids, especially when employed along with fluid loss agents.

Abstract: Adducts of clay, especially of the smectite variety, most especially bentonite, are prepared with an effective amount of at least one activated mixed metal oxide or oxy-hydroxide (AHMMO) formed by dehydrating hydrotalcite or a mixture comprising magnesium oxide and aluminum oxide, or a crystalline mixed metal hydroxide conforming substantially to the formulaLi.sub.m D.sub.d T(OH).sub.(m+2d+3+n.a) (A.sup.n).sub.a. xH.sub.2 Owhere m is zero to one, D is a divalent metal, d is from zero to 4, T is a trivalent metal, A represents at least one anion or negative-valence radical of valence n, where n is 1 or more, (m+2d+3+n.a) is equal to or greater than 3, (m+d) is greater than zero, and xH.sub.2 O represents excess waters of hydration. These adducts are useful, e.g., in drilling muds and in viscosity modification of a wide variety of fluids.