This picture frame is all made with cardboard and the mosaic is made with...eggshells!
I've always wished I could make mosaics but I never had the materials to do them so I thought that I could still do whatever I wanted recycling what I don't need anymore.
Just like with all mosaics, you need a lot of patience, but the result is great and the feeling of satisfaction you get looking at it is worth the time and patience, believe me!

Step 1:

First of all you have to make the frame.

Take a piece of cardboard and draw a rectangle: you must consider how big the picture you will frame is. Mine is 13x18 cm (5.11 x 7.1 inches) so, adding 4 cm (1.57 inches) on every side for the frame, my rectangle is 21x26 cm (8.28 x 10.23 inches).

Cut the rectangle and make another identical one so you will have 2, one for the front frame and one for the back.

Take the first rectangle and draw a 13x18 one in the center counting 4 cm from each side. Depending how big your picture will be, your measures will be bigger/smaller. Once you have traced this last rectangle, cut it out and you will finally have your frame!

Step 2:

Now let's make the frame stand.

Cut a rectangle 7x17 cm (2.75 x 6.69 inches) then cut the cardboard at about 3/4cm (1.18 inches) from one of the short sides to obtain a triangle, as you can see in the picture.

Trace a line on the other side, at about 2cm (0.78 inches) from the border and bend it.

Step 3: Last 3 Rectangles!

Cut 3 rectangles:

one must be 4x26 cm (1.57 x 10.23 inches)
the other 2 ones 4x17 cm (1.57 x 6.69 inches)

Once you have these last 3 pieces you have all the pieces you need for the picture frame!

I put numbers on every piece in the picture so I will be able to explain the next steps better.

Step 4: Let's Put the Pieces Together!

Take piece n.5 and glue it on the longest side at the bottom of n.2. I left the other side free because that's where the picture will pass from.
Now take n.3 and 4 and glue them on the 2 shortest sides.
At last, glue piece n.1 on the 3 pieces you glued previously.

I used hot glue because it dries fast but you could use white glue too.

Step 5:

What you have now is like a "sandwich" of cardboard and the sides are not very nice to see so I cut strips of cardboard to glue on the sides. My frame is 8mm (0.31 inches) thick so that's also the thickness of my strips. These measures vary depending on the kind of cardboard you are using.

Step 6:

Now glue the frame stand behind the picture frame. It doesn't have to be perfectly in the center so don't worry about it. Remember to glue only the small section you bent previously.

Step 7:

The frame is ready, all you have to do now is color it with blue acrylic paint!

Step 8:

Now it's time to decorate the frame with mosaic!

Take clean eggshells and paint them with different shades of blue and white acrylic paint. For my frame I used 5 eggs but there are some pieces left actually.

Once the paint is dry, break the eggshells in little pieces.

Step 9:

Glue the pieces next to each other on the frame.
They don't have to be in a specific order, they can be glued casually but try not to put the same colors too close to each other for a better effect. I used glue stick for this step, it worked perfectly for me but you can also try other kinds of glue, let me know what you think it's best!

It will take some time to cover the frame with the pieces of eggshells but believe me, the result is beautiful!