Pictures with name Opal
(another method is described at the bottom of the page)
The site has other free pictures with names.
How to download the picture?
Hover your mouse over the image, right click. A window will appear in which you need to select 'Save image ...', 'Save image as ...' or 'save image as ...' (in different browsers in different ways). You will then be given the opportunity to choose a location to save the image, select it and click 'Save'.