diff --git a/src/Density/Density.jl b/src/Density/Density.jl
index 806fa684..bec89599 100644
--- a/src/Density/Density.jl
+++ b/src/Density/Density.jl
@@ -27,7 +27,8 @@ export compute_density,     # calculation routines
     Compressible_Density,   # Compressible density
     T_Density,              # T dependent density
     Vector_Density,         # Vector with density
-    MeltDependent_Density   # Melt dependent density
+    MeltDependent_Density,   # Melt dependent density
+    get_α
 
 # Define "empty" computational routines in case nothing is defined
 function compute_density!(
@@ -123,7 +124,6 @@ end
 @inline (ρ::PT_Density)(args)                = ρ(; args...)
 @inline compute_density(s::PT_Density, args) = s(args)
 
-
 # Print info
 function show(io::IO, g::PT_Density)
     return print(
@@ -403,4 +403,14 @@ for type in (ConstantDensity, PT_Density, Compressible_Density, T_Density, MeltD
     @extractors(type, :Density)
 end
 
+import GeoParams.get_α
+
+function get_α(rho::MeltDependent_Density; ϕ::T=0.0, kwargs...) where {T}
+    αsolid = rho.ρsolid.α.val
+    αmelt  = rho.ρmelt.α.val
+    return @muladd ϕ * αmelt + (1-ϕ) * αsolid
+end
+
+get_α(rho::MeltDependent_Density, args) = get_α(rho; args...)
+
 end
diff --git a/src/GeoParams.jl b/src/GeoParams.jl
index 754c28a7..89ebfc2f 100644
--- a/src/GeoParams.jl
+++ b/src/GeoParams.jl
@@ -115,7 +115,6 @@ export MaterialParams, SetMaterialParams, No_MaterialParam, MaterialParamsInfo
 using .MaterialParameters.PhaseDiagrams
 export PhaseDiagram_LookupTable, PerpleX_LaMEM_Diagram
 
-
 # Density
 using .MaterialParameters.Density
 export compute_density,                                # computational routines
@@ -445,4 +444,5 @@ export ntuple_idx
 #     PeierlsCreep_info,
 #     NonLinearPeierlsCreep_info
 
+
 end # module
diff --git a/src/Utils.jl b/src/Utils.jl
index dcc1f6f9..2a4a6cbc 100644
--- a/src/Utils.jl
+++ b/src/Utils.jl
@@ -151,4 +151,4 @@ function add_extractor_functions(::Type{_T}, param_field) where _T
             end
         end
     end
-end
\ No newline at end of file
+end
diff --git a/test/test_Density.jl b/test/test_Density.jl
index 442a78a8..634bc716 100644
--- a/test/test_Density.jl
+++ b/test/test_Density.jl
@@ -325,6 +325,13 @@ using Test, GeoParams, StaticArrays, LaTeXStrings
     @test ρmelt ≈ 2198.68
     @test ρ == (1-args.ϕ)*ρsolid + args.ϕ*ρmelt
 
+    x = MeltDependent_Density(
+        ρsolid = PT_Density(α= 1e-3), 
+        ρmelt  = PT_Density(α= 1e-2), 
+    )
+    @test GeoParams.get_α(x, (;ϕ = 1)) == 1e-2
+    @test GeoParams.get_α(x, (;ϕ = 0)) == 1e-3 
+    @test GeoParams.get_α(x, (;ϕ = 0.5)) == 0.0055
 
     rheologies = (
         SetMaterialParams(;