Experimental data on the extraction of radium/polonium?

I'm having difficulty finding some secondary data on the extraction of radium or polonium. Nothing specific, really just any practical data available on the topic. Historical data would be preferable, however modern data would still be great. By 'data' I just been any experimental data on how the process of radium/polonium extraction takes place (masses of each element in the ore, radioactivity levels, anthing!)

Thanks!