CtrEditor/ObjetosSim/ucBotella.xaml

<UserControl x:Class="CtrEditor.ObjetosSim.ucBotella"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             DataContext="{Binding RelativeSource={RelativeSource Self}}">
    <Border Background="Brown" CornerRadius="10" Height="10" Width="10"/>
</UserControl>