Mosaic Star Quilt Block Pattern

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How to Sew a Mosaic Star Quilt Block

The Mosaic Star quilt block features a central star motif surrounded by a mosaic-like border. While it may look complex, it breaks down into simple steps once you understand its component parts.

Materials Needed

• Fabric in various colors and prints (at least 4 contrasting fabrics)
• Rotary cutter and cutting mat
• Ruler
• Sewing machine and thread
• Iron and ironing board
• Fabric pen or pencil

Step 1: Choose Your Fabrics

Select at least four different fabrics in contrasting colors and prints. Choose fabrics that work well together and complement each other across the star and border.

Step 2: Cut Your Fabrics

Using your rotary cutter, ruler, and mat, cut the following pieces:

• Center square (for the star): one 4½" square
• Star points: eight 2½" squares
• Mosaic squares: sixteen 2½" squares
• Border strips: four 2½" × 4½" rectangles

Step 3: Assemble the Star

Sew together the 2½" star point squares to form eight star arms. Join the arms together to create the central star motif. Press all seams open.

Step 4: Add the Mosaic Border

Sew together four rows of four 2½" mosaic squares each. Press seams open. Sew the mosaic border strips to the top and bottom of the star, then attach the remaining two strips to the sides. Press all seams open after each step.

Step 5: Finish the Block

Trim the completed block to 12½" square and give it a final press. Your Mosaic Star quilt block is complete!

Step 6: Make More Blocks (Optional)

Repeat these steps to make as many blocks as needed for your quilt. Use the same fabrics throughout for a cohesive look, or mix and match for a scrappy style.

Step 7: Assemble the Quilt Top (Optional)

Arrange your completed blocks in the desired layout and sew them together with a ¼" seam allowance. Press seams open.

Step 8: Quilt and Bind (Optional)

Layer your quilt top with batting and backing, quilt using your preferred method, then bind the edges to finish.

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.