I want to increase the size of my FontAwesome icons

I am currently testing on Android.
I want to put a FA icon in my button but when it appears it is far too small. So I try to set a FontSize style, but this does not make any difference. What am I doing wrong here?

 <?xml version="1.0" encoding="utf-8" ?>
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
             xmlns:controls="clr-namespace:XamForms.Controls;assembly=XamForms.Controls.Calendar"
             xmlns:Control="clr-namespace:Xamstrap;assembly=Xamstrap"
             xmlns:Attached="clr-namespace:Xamstrap.AttachedProperties;assembly=Xamstrap"
             xmlns:c="clr-namespace:Sir.Mobile.CustomRenderers"
             xmlns:prism="clr-namespace:Prism.Mvvm;assembly=Prism.Forms"
             prism:ViewModelLocator.AutowireViewModel="True"
             x:Class="Sir.Mobile.Views.InspectionDate"
             ControlTemplate="{StaticResource MainHeader}"
             Title="Inspection Date">
    <ContentPage.Resources>
        <OnPlatform x:Key="FontAwesomeString" x:TypeArguments="x:String">
            <On Platform="iOS" Value="FontAwesome" />
            <On Platform="Android" Value="FontAwesome.ttf#FontAwesome" />
            <On Platform="UWP, WinRT, WinPhone" Value="Assets/Fonts/FontAwesome.ttf#FontAwesome" />
        </OnPlatform>
        <Style x:Key="FontAwesome" TargetType="Button">
            <Setter Property="FontFamily" Value="{StaticResource FontAwesomeString}" />
            <Setter Property="FontSize" Value="50" />
        </Style>
        <!-- Can now use style sheets, see https://docs.microsoft.com/en-us/xamarin/xamarin-forms/user-interface/styles/css/index -->
        <StyleSheet Source="/Assets/Site.css" />
    </ContentPage.Resources>
    <ContentPage.Content>
        <StackLayout Orientation="Vertical"  HorizontalOptions="StartAndExpand">
            <Label Text="{Binding HeaderTitle3}" StyleClass="headerText"  Margin="0, 0, 0, 0"></Label>
            <StackLayout Orientation="Horizontal">
                <StackLayout>
                    <controls:Calendar  SelectedDate="{Binding DateOfVisit, Mode=TwoWay}"
                                    HorizontalOptions="FillAndExpand" VerticalOptions="CenterAndExpand"
                                    x:Name="calendar" DateCommand="{Binding DateOfVisitCommand}" />
                </StackLayout>
                <StackLayout>
                    <Button Command="{Binding OnDateOfVisitCommand}" Style="{Binding FontAwesome}"
                        Text="&#xF060;"  Attached:ResponsiveProperty.Class="btn-sm btn-primary" ></Button>
                </StackLayout>
            </StackLayout>
        </StackLayout>
    </ContentPage.Content>
</ContentPage>