diff --git a/block.go b/block.go
index 6f21164909..1351efae7b 100644
--- a/block.go
+++ b/block.go
@@ -248,8 +248,8 @@ Outer:
 		for _, chk := range chunks {
 			if intervalOverlap(mint, maxt, chk.MinTime, chk.MaxTime) {
 				// Delete only until the current vlaues and not beyond.
-				mint, maxt = clampInterval(mint, maxt, chunks[0].MinTime, chunks[len(chunks)-1].MaxTime)
-				stones[p.At()] = intervals{{mint, maxt}}
+				tmin, tmax := clampInterval(mint, maxt, chunks[0].MinTime, chunks[len(chunks)-1].MaxTime)
+				stones[p.At()] = intervals{{tmin, tmax}}
 				continue Outer
 			}
 		}
diff --git a/head.go b/head.go
index 833f024112..7f93d1658a 100644
--- a/head.go
+++ b/head.go
@@ -243,8 +243,8 @@ Outer:
 		}
 
 		// Delete only until the current values and not beyond.
-		mint, maxt = clampInterval(mint, maxt, h.series[ref].chunks[0].minTime, h.series[ref].head().maxTime)
-		stones = append(stones, Stone{ref, intervals{{mint, maxt}}})
+		tmin, tmax := clampInterval(mint, maxt, h.series[ref].chunks[0].minTime, h.series[ref].head().maxTime)
+		stones = append(stones, Stone{ref, intervals{{tmin, tmax}}})
 	}
 
 	if p.Err() != nil {