Index: wp-includes/media.php
===================================================================
--- wp-includes/media.php	(revision 22874)
+++ wp-includes/media.php	(working copy)
@@ -1507,7 +1507,7 @@
 	<script type="text/html" id="tmpl-media-modal">
 		<div class="media-modal">
 			<h3 class="media-modal-title">{{ data.title }}</h3>
-			<a class="media-modal-close" href="" title="<?php esc_attr_e('Close'); ?>">&times;</a>
+			<a class="media-modal-close" href="" title="<?php esc_attr_e('Close'); ?>"></a>
 		</div>
 		<div class="media-modal-backdrop">
 			<div></div>
@@ -1615,7 +1615,7 @@
 			<# } #>
 
 			<# if ( data.buttons.check ) { #>
-				<a class="check" href="#"><span>&#10003;</span><span class="dash">&ndash;</span></a>
+				<a class="check" href="#"><div></div><div class="dash"></div></a>
 			<# } #>
 		</div>
 		<# if ( data.describe ) { #>
Index: wp-includes/css/media-views.css
===================================================================
--- wp-includes/css/media-views.css	(revision 22874)
+++ wp-includes/css/media-views.css	(working copy)
@@ -103,6 +103,12 @@
 	text-shadow: 0 0 16px rgba( 0, 0, 0, 0.6 );
 }
 
+.media-modal-close {
+	background: url(../images/uploader-icons.png) no-repeat -80px 0;
+	width: 15px;
+	top: -27px;
+}
+
 a.media-modal-close {
 	color: #fff;
 }
@@ -648,14 +654,24 @@
 	background-image:   linear-gradient(to bottom, #f1f1f1, #e1e1e1);
 }
 
+.attachment .check div {
+	background: url(../images/uploader-icons.png) no-repeat 0 0;
+	height: 15px;
+	width: 15px;
+	margin: 5px 4px;
+}
+
 .attachment .check .dash {
+	background: url(../images/uploader-icons.png) no-repeat -39px 0;
+	height: 15px;
+	width: 15px;
 	font-weight: bold;
 	font-size: 18px;
 	line-height: 22px;
 }
 
 .attachment .check .dash,
-.attachment .check:hover span {
+.attachment .check:hover div {
 	display: none;
 }
 
@@ -677,6 +693,14 @@
 	background-image:   linear-gradient(to bottom, #1e8cbe, #0074a2);
 }
 
+.attachment.details .check div {
+	background: url(../images/uploader-icons.png) no-repeat -21px 0;
+}
+
+.attachment.details .check .dash {
+	background: url(../images/uploader-icons.png) no-repeat -60px 0;
+}
+
 .media-frame .describe {
 	position: relative;
 	display: block;
@@ -688,6 +712,35 @@
 }
 
 /**
+ * HiDPI Displays
+ */
+@media print,
+  (-o-min-device-pixel-ratio: 5/4),
+  (-webkit-min-device-pixel-ratio: 1.25),
+  (min-resolution: 120dpi) {
+	.attachment .check div {
+		background: url(../images/uploader-icons-2x.png) no-repeat 0 0;
+		background-size: 95px 15px;
+	}
+	.attachment .check .dash {
+		background: url(../images/uploader-icons-2x.png) no-repeat -39px 0;
+		background-size: 95px 15px;
+	}
+	.attachment.details .check div {
+		background: url(../images/uploader-icons-2x.png) no-repeat -21px 0;
+		background-size: 95px 15px;
+	}
+	.attachment.details .check .dash {
+		background: url(../images/uploader-icons-2x.png) no-repeat -60px 0;
+		background-size: 95px 15px;
+	}
+	.media-modal-close {
+		background: url(../images/uploader-icons.png) no-repeat -80px 0;
+		background-size: 95px 15px;
+	}
+}
+
+/**
  * Attachments Browser
  */
 .media-frame .attachments-browser {