diff --git a/opm/core/fluid/RockBasic.hpp b/opm/core/fluid/RockBasic.hpp
new file mode 100644
index 000000000..965637807
--- /dev/null
+++ b/opm/core/fluid/RockBasic.hpp
@@ -0,0 +1,79 @@
+/*
+  Copyright 2012 SINTEF ICT, Applied Mathematics.
+
+  This file is part of the Open Porous Media project (OPM).
+
+  OPM is free software: you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation, either version 3 of the License, or
+  (at your option) any later version.
+
+  OPM is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with OPM.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#ifndef OPM_ROCKBASIC_HEADER_INCLUDED
+#define OPM_ROCKBASIC_HEADER_INCLUDED
+
+
+#include <vector>
+
+
+namespace Opm
+{
+
+    class RockBasic
+    {
+    public:
+        /// Default constructor.
+        RockBasic();
+
+        /// Initialize with homogenous porosity and permeability.
+        void init(const int dimensions,
+		  const int num_cells,
+		  const double poro,
+		  const double perm);
+
+        /// \return   D, the number of spatial dimensions.
+        int numDimensions() const
+        {
+            return dimensions_;
+        }
+
+        /// \return   N, the number of cells.
+        int numCells() const
+        {
+            return porosity_.size();
+        }
+
+        /// \return   Array of N porosity values.
+        const double* porosity() const
+        {
+            return &porosity_[0];
+        }
+
+        /// \return   Array of ND^2 permeability values.
+        ///           The D^2 permeability values for a cell are organized as a matrix,
+        ///           which is symmetric (so ordering does not matter).
+        const double* permeability() const
+        {
+            return &permeability_[0];
+        }
+
+    private:
+	int dimensions_;
+        std::vector<double> porosity_;
+        std::vector<double> permeability_;
+    };
+
+
+
+} // namespace Opm
+
+
+#endif // OPM_ROCKBASIC_HEADER_INCLUDED