Umbrae is a term borrowed from astronomy which basically means from shadow to light. It is usually used to describe the light and reflection on the moon or a planet.
So when you apply the term to stamping you refer to the graduation of a colour from a darker tone to the lighter tone. It is very popular and a great background for cards, scrap book pages and off the page projects alike.
Here is a clean and simple card that I have made using the inking technique:
Midnight Muse is the base card stock here. I mounted Whisper White on top which I stamped the chevron stamp on in Midnight Muse, Pacific Point and Marina Mist. The piece of ribbon running alongside the stamped image is Stitched Satin Midnight Muse ribbon.
I embossed the larger oval stamp from the Oh Hello stamp set in white on Midnight Muse and then cut the oval out with Oval Framelits. The greeting was stamped on Whisper White and punched using the Wide Oval Punch. I punched the same size in the Silver Glimmer card stock to add a bit of bling.
To balance the bling I positioned diamante rhinestones on the card in three spots.
Clean and simple and a great card for a catch up message!