Learn How to Make an Easy Mosaic Quilt Block

Inside: How to Make a Modern Mosaic Quilt Block

When looking at quilt blocks for this series I always search for something unique or special about a block.

This quilt block is one with lots of names, and none of them are consistent. In my EQ8 software this block is called Mosaic #5.

If you look up mosaic quilt blocks, you’ll see them named Mosaic #1, Mosaic #2, etc. And none of these number-names are consistent.

I consulted my Encyclopedia of Pieced Quilt Patterns and found that mosaic blocks, indeed, go by numbers. But, it’s inconsistent on which one is actually Mosaic #5.

So, I’m calling this one the Modern Mosaic Quilt Block. Bottom line, I know you’re going to love how easy this quilt block is to make.

And be sure to grab the FREE PDF assembly diagram below.

Learn How to Make an Easy Mosaic Quilt Block

Want an ad-free, printable copy of this tutorial? Scroll to the bottom of this post for more details!

How to Make a Modern Mosaic Quilt Block

I chose this block because it’s all half square triangles (HSTs). That’s it, if you can piece HSTs, ya’ got this!

The Modern Mosaic Quilt Block offers you some variety because it can be dramatically different depending on your fabric choices.

Fabric Requirements

This block is very economical. I used some solid fat quarters that were in my stash. As long as you choose fabrics that have a contrast, anything will work.

Solid Fabric #1 (Coral)
Solid Fabric #2 (Dark Turquoise)
Solid Fabric #3 (Light Turquoise)
White Fabric (Kona White #1387)

Basic Sewing Supplies Needed

Sewing Machine
- It’s nice to use a 1/4″ sewing foot to help maintain a perfect seam allowance
Cotton Thread
- I prefer Aurifil 50 wt. thread
Sewing Pins
Rotary Cutter with sharp blade
Acrylic Ruler
Rotary Cutting Mat
Iron & Ironing Board

Cutting and Marking

Iron your fabrics nice and flat to remove any wrinkles. Use the cutting measurements below to get your pieces cut out and in order.

Qty (2) 4″ x 4″ Coral (A)
Qty (2) 4″ x 4″ Light Turquoise (B)
Qty (6) 4″ x 4″ Dark Turquoise (C)
Qty (6) 4″ x 4″ White (D)

Get a FREE PDF Download

Click the pink button below to get a FREE Printable PDF that includes assembly diagrams for the Modern Mosaic Quilt Block with HST’s 2-at-a-Time.

>>> Click here to download the FREE Modern Mosaic Assembly Diagram

Step 1: Half Square Triangles (HST) 2-at-a-Time

Follow the diagram below to make the Coral/Light Turquoise HSTs (2) and the Dark Turquoise/White HSTs (6).

Place a light and a dark fabric square right sides together.
Use a pencil or water soluble marker, draw a diagonal line from one corner to the opposite corner.
On both sides of the diagonal line, stitch a scant 1/4″ seam. See How to Sew the Perfect Quilting Seam Allowance for more details.
Using a quilter’s ruler and rotary cutter, cut along the pencil line.
Press seams to one side.
Trim each HST down to 3 1/2″ x 3 1/2″.

Note: The best way to get perfect points is to use a quality ruler such as this one by Creative Grids when trimming your HSTs. See the image below.

Step 2: Modern Mosaic Block Assembly

The only challenge (besides choosing fabrics!) is matching points. As long as you pin your points, it should go together smoothly.

Arrange your individual Mosaic squares in correct layout (pictured below).
Using a quarter inch seam allowance, sew together the top row. Press seams in same direction. Repeat for the next three rows. Alternate pressing direction on each row.
Join rows using a quarter inch seam allowance. Take time to nest your seams. Pinning will help with matching.
Press your completed block and trim down block to 12.5″ square (if necessary).