Mosaic #3 Quilt Block Pattern

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How to Sew a Mosaic #3 Quilt Block

The Mosaic #3 quilt block is a visually striking design using small fabric squares in at least three colors arranged in a gradient diamond pattern. The colors flow from light to dark across the block, creating a beautiful mosaic effect that looks stunning in any quilt!

Materials Needed

• Fabric pieces in at least 3 different colors
• Rotary cutter or fabric scissors and cutting mat
• Quilting ruler and sewing machine
• Thread and iron with ironing board

Step-by-Step Instructions

1. Cut your fabric squares. Cut fabric pieces into small squares of the same size. You'll need at least three different colors to create the gradient effect.
2. Arrange the squares. Lay out the squares in a diamond shape, with the colors forming a gradient from light to dark.
3. Sew the squares into rows using a ¼" seam allowance. Press the seams open with an iron.
4. Sew the rows together, carefully matching the seams as you go. Press the seams open.
5. Trim the block to ensure it is square. The finished size for a Mosaic #3 block is 12½" square.
6. Repeat to create as many blocks as needed for your quilt.
7. Arrange the blocks, alternating the direction of the diamond shape to create a dynamic visual effect across the quilt top.
8. Sew the blocks together using a ¼" seam allowance. Press the seams open.
9. Add batting and backing to create a quilt sandwich, then quilt as desired.
10. Bind the edges to finish your quilt.

Congratulations — you've sewn a beautiful Mosaic #3 quilt block!

How to Resize Quilt Blocks

The first step in modifying any quilt block is to decide on your finished block size. You can base this on doubling a pattern, cutting it in half, or working with your available fabric.

Note: When working from a pattern's cutting instructions, remove the seam allowance before scaling. For example, if your pattern calls for 3½″ squares, subtract the seam allowance (½″), double the finished size (3″ → 6″), then add the seam allowance back (½″) — giving you a 6½″ cut piece.

Resizing Square Blocks

Add ½″ to your finished block measurement. For a 4″ finished square, cut a 4½″ square of fabric.

Resizing Rectangular Blocks

Add ½″ to both the length and width. To double a 3″ × 4″ block, cut a 6½″ × 8½″ rectangle.

Resizing Half-Square Triangle Blocks

Add 7/8″ to the desired finished block size. For a 4″ finished HST block, cut 4⅞″ squares.

Resizing Quarter Square Triangle Blocks

Add 1¼″ to the desired finished block size. For a 4″ finished block, cut 5¼″ squares.