I've been experimenting with Microdata and thought I would try it on my blog. It turns out the template I was using already added some markup. It wasn't great and so I fixed up what I could.

To try and push my luck I have added more markup to my latest post but Google's Structured Data Testing Tool (SDTT) is unhappy about the `itemprop='image'` attributes and I'm not sure why.

[![Structured Testing Tool errors][5]][5]

[Results page][6].

It is my understanding, ignoring all the code in between, that I have structured the data thus:

    <div itemscope='itemscope' itemtype='http://schema.org/BlogPosting'>
      <div itemprop='articleBody'>
        <a href="1.png" itemprop="url"><img itemprop="image sharedContent" src="1.png" /></a>
        <a href="2.png" itemprop="url"><img itemprop="image sharedContent" src="2.png" /></a>
        <a href="3.png" itemprop="url"><img itemprop="image sharedContent" src="3.png" /></a>
      </div>
    </div>

And this looks correct to me.
`BlogPosting` can have the properties `articleBody` and `image` according to https://schema.org/BlogPosting, but according to the SDTT:

> The attribute itemtype has an invalid value.

Indeed, I have just tried the SDTT with the above example code and it is failing to validate.

[![Example code in the SDTT][7]][7]

So I'm obviously missing something. What am I doing wrong?

  [5]: https://i.sstatic.net/uXfwb.png
  [6]: https://developers.google.com/structured-data/testing-tool?url=http%253A%252F%252Fkennystechtalk.blogspot.co.uk%252F2016%252F02%252Fyoutube-poll-cards-are-gert-lush-honest.html
  [7]: https://i.sstatic.net/wlFv2.png